Lenovo ThinkSystem SR635 V3 Server

The Lenovo ThinkSystem SR635 V3 is a 1-socket 1U server that features the AMD EPYC 9004 "Genoa" family of processors. With up to 128 processor cores and support for the new PCIe 5.0 standard for I/O, the SR635 V3 offers the ultimate in one-socket server performance in a 1U form factor. The server is ideal for dense workloads that can take advantage of GPU processing and high-performance NVMe drives.

Suggested uses: AI Inference, VDI, OLTP, Analytics, HPC, software-defined storage

Figure 1. Lenovo ThinkSystem SR635 V3

Combining performance and flexibility, the SR635 V3 server is a great choice for enterprises of all sizes. The server offers a broad selection of drive and slot configurations and offers high performance features that industries such as finance, healthcare and telco need. Outstanding reliability, availability, and serviceability (RAS) and high-efficiency design can improve your business environment and can help save operational costs.

Scalability and performance

The following features boost performance, improve scalability and reduce costs: 

• Supports one fourth-generation AMD EPYC 9004 processor
  • Up to 128 cores and 256 threads
  • Core speed of up to 4.1 GHz
  • TDP rating of up to 360 W
• Support for DDR5 memory DIMMs to maximize the performance of the memory subsystem:
  • 12 DDR5 memory DIMMs
  • 12 memory channels (1 DIMM per channel)
  • DIMM speeds up to 4800 MHz
  • Using 256GB 3DS RDIMMs, the server supports up to 3TB of system memory
• Supports up to four single-width GPUs (3 in rear slots, 1 in front slots), each up to 75W for substantial processing power in a 1U system.
• The server is Compute Express Link (CXL) v1.1 Ready. With CXL 1.1 for next-generation workloads, you can reduce compute latency in the data center and lower TCO. CXL is a protocol that runs across the standard PCIe physical layer and can support both standard PCIe devices as well as CXL devices on the same link.
• Supports up to 12x 2.5-inch hot-swap drive bays, by using combinations of front-accessible (up to 10 bays) and rear-accessible (2 bays).
• Supports 16x NVMe drives without the need for additional NVMe adapters and without oversubscription of PCIe lanes (1:1 connectivity). The use of NVMe drives maximizes drive I/O performance, in terms of throughput, bandwidth, and latency.
• Supports 12x SATA drives using the onboard SATA controller (no additional adapter needed), enabling lower cost, high capacity storage solution for cold storage workloads.
• Supports 12x SAS drives using a variety of support RAID controllers or SAS HBAs.
• Supports high-speed RAID controllers from Lenovo and Broadcom providing 12 Gb SAS connectivity to the drive backplanes. A variety of PCIe 3.0 and PCIe 4.0 RAID adapters are available.
• Supports two externally accessible 7mm hot-swap drives for operating system boot functions or data storage. Optional RAID with the addition of a RAID adapter installed in a slot.
• Supports M.2 drives for convenient operating system boot functions or data storage. Available M.2 adapters support either one M.2 drive or two M.2 drives. Optional RAID with the addition of a RAID adapter installed in a slot.
• Supports up to 5x PCIe slots, 3x at the rear of the server and 2x at the front of the server. Also supports 1x OCP 3.0 slot, either in the front or in the rear.
• The server has a dedicated industry-standard OCP 3.0 small form factor (SFF) slot, with a PCIe 5.0 x16 interface, supporting a variety of Ethernet network adapters. Simple-swap mechanism with thumbscrews and pull-tab enables tool-less installation and removal of the adapter. Supports shared BMC network sideband connectivity to enable out-of-band systems management.
• The server offers PCI Express 5.0 (PCIe Gen 5) I/O expansion capabilities that doubles the theoretical maximum bandwidth of PCIe 4.0 (32GT/s in each direction for PCIe 5.0, compared to 16 GT/s with PCIe 4.0). A PCIe 5.0 x16 slot provides 128 GB/s bandwidth, enough to support a 400GbE network connection.
• The server uses the Lenovo Neptune closed-loop liquid-cooled heatsink design to more effectively remove heat from high-performance processor SKUs.

Availability and serviceability

The server provides many features to simplify serviceability and increase system uptime:

• Designed to run 24 hours a day, 7 days a week
• The server uses ECC memory and supports memory RAS features including Single Device Data Correction (SDDC, also known as Chipkill), Patrol/Demand Scrubbing, Bounded Fault, DRAM Address Command Parity with Replay, DRAM Uncorrected ECC Error Retry, On-die ECC, ECC Error Check and Scrub (ECS), and Post Package Repair.
• The server offers hot-swap drives, supporting RAID redundancy for data protection and greater system uptime.
• Available M.2 configuration with RAID support which can enable two SATA or two NVMe M.2 drives to be configured as a redundant pair.
• The server has up to two hot-swap redundant power supplies and up to seven hot-swap redundant fans to provide availability for business-critical applications.
• Optional front-accessible slots and drives so that most major components and cables (except power) are located at the front of the server
• The power-source-independent light path diagnostics uses LEDs to lead the technician to failed (or failing) components, which simplifies servicing, speeds up problem resolution, and helps improve system availability.
• Solid-state drives (SSDs) offer more reliability than traditional mechanical HDDs for greater uptime.
• Proactive Platform Alerts (including PFA and SMART alerts): Processor, voltage regulators, memory, internal storage (SAS/SATA HDDs and SSDs, NVMe SSDs, M.2 storage, flash storage adapters), fans, power supplies, RAID controllers, server ambient and subcomponent temperatures. Alerts can be surfaced through the XClarity Controller to managers such as Lenovo XClarity Administrator, VMware vCenter, and Microsoft System Center. These proactive alerts let you take appropriate actions in advance of possible failure, thereby increasing server uptime and application availability.
• The built-in XClarity Controller 2 continuously monitors system parameters, triggers alerts, and performs recovery actions in case of failures to minimize downtime.
• Built-in diagnostics in UEFI, using Lenovo XClarity Provisioning Manager, speed up troubleshooting tasks to reduce service time.
• Lenovo XClarity Provisioning Manager supports diagnostics and can save service data to a USB key drive or remote CIFS share folder for troubleshooting and reduce service time.
• Auto restart in the event of a momentary loss of AC power (based on power policy setting in the XClarity Controller service processor)
• Offers a diagnostics port on the front of the server to allow you to attach an external diagnostics handset for enhanced systems management capabilities.
• Support for the XClarity Administrator Mobile app running on a supported smartphone and connected to the server through the service-enabled USB port, enables additional local systems management functions.
• Three-year or one-year customer-replaceable unit and onsite limited warranty, 9 x 5 next business day. Optional service upgrades are available.

Manageability and security

Systems management features simplify local and remote management:

• The server includes an XClarity Controller 2 (XCC2) to monitor server availability. Optional upgrade to XCC Platinum to provide remote control (keyboard video mouse) functions, support for the mounting of remote media files, FIPS 140-3 security, enhanced NIST 800-193 support, boot capture, and other management and security features.
• Lenovo XClarity Administrator offers comprehensive hardware management tools that help to increase uptime, reduce costs and improve productivity through advanced server management capabilities.
• UEFI-based Lenovo XClarity Provisioning Manager, accessible from F1 during boot, provides system inventory information, graphical UEFI Setup, platform update function, RAID Setup wizard, operating system installation function, and diagnostic functions.
• Support for Lenovo XClarity Energy Manager which captures real-time power and temperature data from the server and provides automated controls to lower energy costs.
• An integrated industry-standard Unified Extensible Firmware Interface (UEFI) enables improved setup, configuration, and updates, and simplifies error handling.
• Support for industry standard management protocols, IPMI 2.0, SNMP 3.0, Redfish REST API, serial console via IPMI
• An integrated hardware Trusted Platform Module (TPM) supporting TPM 2.0 enables advanced cryptographic functionality, such as digital signatures and remote attestation.
• Administrator and power-on passwords help protect from unauthorized access to the server.
• Supports AMD Secure Root-of-Trust, Secure Run and Secure Move features to minimize potential attacks and protect data as the OS is booted, as applications are run and as applications are migrated from server to server.
• Supports Secure Boot to ensure only a digitally signed operating system can be used.
• Industry-standard Advanced Encryption Standard (AES) NI support for faster, stronger encryption.
• Additional physical security features are a chassis intrusion switch and a lockable front bezel.

Energy efficiency

The following energy-efficiency features help save energy, reduce operational costs, and increase energy availability:

• Energy-efficient planar components help lower operational costs.
• High-efficiency power supplies with 80 PLUS Titanium certifications
• Low-voltage 1.1 V DDR5 memory offers energy savings compared to 1.2 V DDR4 DIMMs, an approximately 20% decrease in power consumption
• Solid-state drives (SSDs) consume as much as 80% less power than traditional spinning 2.5-inch HDDs.
• The server uses hexagonal ventilation holes, which can be grouped more densely than round holes, providing more efficient airflow through the system and thus keeping your system cooler.
• Optional Lenovo XClarity Energy Manager provides advanced data center power notification and analysis to help achieve lower heat output and reduced cooling needs.

The ThinkSystem SR635 V3 improves on the previous generation SR635, as summarized in the following table.

The following figure shows the architectural block diagram of the SR635 V3, showing the major components and their connections.

Figure 5. SR635 V3 system architectural block diagram

The following table lists the standard specifications.

ThinkSystem SR635 V3 models can be configured by using the Lenovo Data Center Solution Configurator (DCSC).

Topics in this section:

• CTO models
• CTO models for Windows 10 and Windows 11
• Base feature codes
• Preconfigured models

CTO models

ThinkSystem SR635 V3 models can be configured by using the Lenovo Data Center Solution Configurator (DCSC).

Configure-to-order (CTO) models are used to create models with factory-integrated server customizations. For CTO models, two types of base CTO models are available for the SR635 V3 as listed in the columns in the following table:

• General purpose base CTO models are for general business (non-HPC) and is selectable by choosing General Purpose mode in DCSC.
• AI and HPC base models are intended for Artificial Intelligence (AI) and High Performance Computing (HPC) configurations and solutions are enabled using the AI & HPC Hardware - ThinkSystem Hardware mode in DCSC. These configurations, along with Lenovo EveryScale Solutions, can also be built using System x and Cluster Solutions Configurator (x-config). Tip: Some HPC and AI models are not listed in DCSC and can only be configured in x-config.

Preconfigured server models may also be available for the SR635 V3, however these are region-specific; that is, each region may define their own server models, and not all server models are available in every region.

The following table lists the base CTO models of the ThinkSystem SR635 V3 server.

CTO models for Windows 10 and Windows 11

The SR635 V3 can run Windows 10 and Windows 11, however only a subset of adapters and drives can be installed. For ease of configuration, the following Base CTO models have been announced to assist building a configuration that can be used with the client operating systems. For more information, see the Windows 10 and Windows 11 section.

Base feature codes

Models of the SR635 V3 are defined based on whether or not front PCIe slots are configured. The feature codes for these chassis bases are as listed in the following table.

Preconfigured models

The following tables list the available preconfigured models, grouped by region.

• Models for Australia and New Zealand

Refer to the Specifications section for information about standard features of the server.

The SR635 V3 supports processors in the fourth-generation AMD EPYC family of processors. The server supports one processor.

Topics in this section:

• Processor options
• Processor features
• Thermal requirements by processor
• Closed-loop liquid-cooled heatsink
• UEFI operating modes
• Platform Secure Boot

The SR635 V3 supports different processor heatsink solutions, depending on the configuration, as listed in the following table.

The selection of the heatsink will be automatically derived by the configurator and depends on the processor and other components selected. Use the tables in the Lenovo Docs site to determine the requirements for each heatsink:
https://pubs.lenovo.com/sr635-v3/thermal_rules

Closed-loop liquid-cooled heatsink

The closed-loop liquid-cooled heatsink is primarily used for processors with a TDP of 320W or more. Without the closed-loop heatsink, the use of processors ≥ 320W TDP (except for 9654 and 9654P) requires that only 4x front 2.5-inch drive bays be configured. The use of the closed-loop heatsink allows for 10x SAS/SATA or NVMe drives bays.

The only exception to this rule is the use of the 9654 and 9654P 360W processors which allow the use of 10x 2.5-inch drive bays, provided the ambient temperature be no more than 25°C.

The following figure shows the placement of the components in the closed-loop system. A cold plate is mounted on top of the processor and it is connected via aluminum tubes to a radiator that is placed in front of the system fans. The tubes contain a mixture of water and ethylene glycol (EGW). The liquid is actively pumped through the pipes in a closed loop to remove the heat from the processors.

Figure 6. SR635 V3 with closed loop heatsink (feature BS34)

The closed-loop liquid-cooled heatsink has the following requirements:

• One of the following 2.5-inch front drive bay configurations:
  • 10x 2.5" NVMe Gen4 (not Gen5)
  • 10x 2.5" SAS/SATA
  • 8x 2.5'' SAS/SATA
  • 6x SAS/SATA + 4x AnyBay
  • 6x SAS/SATA + 2x AnyBay + 2x NVMe
• EDSFF front drive bays are not supported
• If a RAID 940 or 9350 adapter is configured:
  • RAID supercap must be installed in slot 3
  • 7mm drives are not supported
• The following components are not supported:
  • 256GB 3DS RDIMMs
  • Rear 2.5-inch drives
  • M.2 drives
  • Any internal RAID/HBAs (CFF form factor)

For specific requirements, see the Thermal Rules page at https://pubs.lenovo.com/sr635-v3/thermal_rules.

The following table lists the feature codes that allow you to specify the mode you wish to preset in the factory for CTO orders.

The preset modes for the SR635 V3 are as follows:

• Maximum Efficiency Mode (feature BFYA): Maximizes performance/watt efficiency while maintaining reasonable performance
• Maximum Performance Mode (feature BFYB): Achieves maximum performance but with higher power consumption and lower energy efficiency.

For details about these preset modes, and all other performance and power efficiency UEFI settings offered in the SR635 V3, see the paper "Tuning UEFI Settings for Performance and Energy Efficiency on AMD Processor-Based ThinkSystem Servers", available from https://lenovopress.lenovo.com/lp1267.

Platform Secure Boot

Platform Secure Boot (PSB) is a feature of AMD EPYC processors that helps defend against threats to firmware. It is designed to provide protection in response to growing firmware-level remote attacks being seen across the industry. AMD Secure Boot extends the AMD silicon root of trust to help protect the system by establishing an unbroken chain of trust from the AMD silicon root of trust to the BIOS. The UEFI secure boot helps continue the chain of trust from the system BIOS to the OS Bootloader. This feature helps defend against remote attackers seeking to embed malware into firmware.

With PSB enabled, the processor is cryptographically bound to the server firmware code signing key once the processors are installed in the server and the server is powered on. From that point on, that processor can only be used with motherboards that use the same code signing key.

Disabling PSB will stop the protection against remote and local attackers seeking to embed malware into a platform’s firmware, BIOS and even UEFI functions. Disabling PSB also allows you to install the processor in another server that you purchased from Lenovo, however, we do not recommend you do this by yourself. Please contact the Lenovo service team for further assistance. 

By default, the server has Platform Secure Boot enabled on the installed processors, however for factory orders, you can choose to have the server with PSB disabled. To do this, select the feature code listed in the following table. PSB can be later enabled in System Setup if desired.

If you add a second processor as a field upgrade and your server has PSB enabled, then as soon as you install the processor and power the server on, the processor is then cryptographically bound to the server, and can only be used in that server going forward.

Note: Platform Secure Boot (PSB) is different from the Secure Boot security feature described in the Platform Firmware Resiliency section.

The SR635 V3 uses Lenovo TruDDR5 memory operating at up to 4800 MHz. The server supports up to 12 DIMMs. The processor has 12 memory channels and supports 1 DIMM per channel. The server supports up to 3TB of memory using 12x 256GB 3DS RDIMMs.

The following table lists the memory options that are available for the server.

Lenovo TruDDR5 memory uses the highest quality components that are sourced from Tier 1 DRAM suppliers and only memory that meets the strict requirements of Lenovo is selected. It is compatibility tested and tuned to maximize performance and reliability. From a service and support standpoint, Lenovo TruDDR5 memory automatically assumes the system warranty, and Lenovo provides service and support worldwide.

9x4 RDIMMs (also known as Optimized or EC4 RDIMMs) are a new lower-cost DDR5 memory option supported in ThinkSystem V3 servers. 9x4 DIMMs offer the same performance as standard RDIMMs (known as 10x4 or EC8 modules), however they support lower fault-tolerance characteristics. Standard RDIMMs and 3DS RDIMMs support two 40-bit subchannels (that is, a total of 80 bits), whereas 9x4 RDIMMs support two 36-bit subchannels (a total of 72 bits). The extra bits in the subchannels allow standard RDIMMs and 3DS RDIMMs to support Single Device Data Correction (SDDC), however 9x4 RDIMMs do not support SDDC. Note, however, that all DDR5 DIMMs, including 9x4 RDIMMs, support Bounded Fault correction, which enables the server to correct most common types of DRAM failures.

For more information on DDR5 memory, see the Lenovo Press paper, Introduction to DDR5 Memory, available from https://lenovopress.com/lp1618.

The following rules apply when selecting the memory configuration:

• The SR635 V3 supports quantities 1, 2, 4, 6, 8, 10, 12 DIMMs per processor; other quantities not supported
• The server supports four types of DIMMs: 9x4 RDIMMs, 10x4 RDIMMs, x8 RDIMMs and 3DS RDIMMs; UDIMMs and LRDIMMs are not supported
• Mixing of DIMM types is not supported (for example, 9x4 DIMMs with 10x4 RDIMMs)
• Mixing x4 and x8 DIMMs is not supported
• Mixing of 128GB 3DS RDIMMs and 256GB 3DS RDIMMs is not supported
• Mixing of DIMM rank counts is supported. Follow the required installation order installing the DIMMs with the higher rank counts first.
• Mixing of DIMM capacities is supported, however only two different capacities are supported across all channels of the processor (eg 16GB and 32GB). Follow the required installation order installing the larger DIMMs first.

• The use of the 128GB 3D RDIMM feature BYEE has the following requirements for thermal reasons:
  • Performance fans are required
  • Rear 2.5-inch drives are not supported
  • GPUs are not supported
  • Additional ambient temperature requirements - see https://pubs.lenovo.com/sr635-v3/thermal_rules for information

Note: Memory mirroring and memory rank sparing are not supported.

The SR635 V3 supports 12x 2.5-inch or 16x EDSFF drive bays, depending on the selected chassis and backplane configuration. The server also supports configurations without any drive bays if desired.

All drives are hot-swap and are accessible from the front or from the rear.

The server also supports one or two M.2 drives, installed in an M.2 adapter internal to the server.

In this section:

• NVMe drive support
• Front drive bays
• Rear 2.5-inch and 7mm drive bays
• Storage configurations
• Field upgrades
• RAID flash power module (supercap) support
• M.2 drives
• SED encryption key management with SKLM

The specifics of these configurations are covered in the Storage configurations section.

In addition, the SR635 V3 supports two 7mm NVMe drives for use as boot drives. These two drives optionally support RAID via a separate RAID adapter installed in a PCIe slot.

Front drive bays

The front drive bay zone supports the following configurations. All drives are hot-swap.

• 2.5-inch hot-swap drive bays - 10 drive bays
  • 10x SAS/SATA
  • 6x SAS/SATA + 4x AnyBay (PCIe Gen4)
  • 6x SAS/SATA + 2x AnyBay + 2x NVMe (PCIe Gen4)
  • 10x AnyBay (PCIe Gen4 or Gen5)
  • 10x NVMe (PCIe Gen4)
• 2.5-inch hot-swap drive bays - 8 drive bays with optional integrated diagnostics panel
  • 8x SAS/SATA
• 2.5-inch hot-swap drive bays - 4 drive bays with optional support for front PCIe slots
  • 4x SAS/SATA
  • 4x NVMe (PCIe Gen4 or Gen 5)
• EDSFF drive bays
  • 16x E1.S (9.5mm or 15mm) hot-swap NVMe drive bays (PCIe Gen4)
• Drive-less 2.5-inch configuration - No backplane and no drives (supports field upgrades)

These configurations are shown in the following three figure. The feature codes listed correspond to the feature codes listed in the table below the figures.

The following figure shows the supported 2.5-inch drive bays drive bay configurations without PCIe slot support. 8x 2.5-inch drive configurations can be configured with or without an Integrated Diagnostics Panel with pull-out LCD display. See the Local management section for details.

Figure 7. SR635 V3 front drive bay configurations without front PCIe slots

The following figure shows the supported 2.5-inch drive bays drive bay configurations with front PCIe slot support. Front slots are mutually exclusive with rear slots. See the I/O expansion for details.

Figure 8. SR635 V3 front drive bay configurations with front PCIe slots

The backplanes used to provide these drive bays are listed in the following table.

The backplanes used to provide these drive bays in CTO orders are listed in the following table. Backplanes are also available as part numbers for field upgrades using upgrade kits, as described in the Field upgrades section below.

The SR635 V3 supports two 7mm drive options installed in slot 3:

• 7mm drive backplane supporting SATA or NVMe drives, without integrated RAID. Optional RAID functionality is provided by a separate RAID adapter installed in a slot.
• 7mm drive backplane supporting NVMe drives (no SATA support) with integrated RAID support via an onboard Marvell 88NR2241 NVMe RAID controller

The use of rear 2.5-inch drive bays has the following configuration rules:

• With 2.5-inch rear drive bays, only slot 1 is available. Slot 2 and 3 are not available
• GPUs are not supported

The use of the 7mm rear drive bays has the following configuration rules:

• 7mm rear drive bays occupy slot 3; slots 1 and 2 are available and slot 2 is a low profile slot. Slot 3 is not available.
• M.2 RAID and 7mm RAID are mutually exclusive: they are not supported together in the same configuration
• GPUs are not supported
• For ThinkSystem 7mm SATA/NVMe 2-Bay Rear Enablement Kit v2 (feature BU0N):
  • The 7mm drive bays support either SATA drives or NVMe drives but not both. You specify SATA or NVMe in the configurator using feature codes BTTV (SATA) or BTTW (NVMe).
  • If RAID support is not required, the 7mm drives connect to an onboard port; No additional adapter is required
  • If RAID support is required, select feature code BS7A in the configurator to enable RAID
  • The support of RAID-1 with the 7mm drives requires an additional RAID adapter that is installed in PCIe slot 1 or 2:
    • RAID support for 7mm SATA drives requires a RAID 5350-8i adapter (feature BT7N)
    • RAID support for 7mm NVMe drives requires a RAID 540-8i adapter operating in Tri-Mode (feature BT7P)
  • The RAID adapter used for 7mm drive support cannot be configured for use with other drive bays (not even with M.2)
• For ThinkSystem 1U 7mm Drive Kit w/ NVMe RAID (feature B8Q2)
  • The adapter only supports NVMe drives
  • RAID functionality is integrated into the M.2 adapter using a Marvell 88NR2241 NVMe RAID Controller
• For ThinkSystem 7mm SATA/NVMe 2-Bay Rear Hot-Swap RAID Enablement Kit (feature BYFG)
  • The 7mm drive bays support either SATA drives or NVMe drives but not both.
  • RAID functionality is integrated into the 7mm backplane using a Broadcom RAID Controller

The following tables summarize the storage configurations for the SR635 V3. For details, including processor requirements, M.2 and 7mm support, and controller selections, see the Storage configurations - Details section.

Click to jump down to the details of the 2.5-inch configurations without front slots.

Click to jump down to the details of the 2.5-inch configurations with front slots.

In the table:

• 7mm SATA Non-RAID means the 7mm SATA/NVMe kit (BU0N) with SATA drives. RAID is not supported.
• 7mm NVMe Non-RAID means the 7mm SATA/NVMe kit (BU0N) with NVMe drives. RAID is not supported.
• 7mm RAID means the 7mm NVMe RAID B8Q2) with NVMe drives. SATA drives not supported. RAID-0 and RAID-1 are supported with the integrated Marvell RAID controller.
• 7mm SATA with SFF RAID 5350-8i means the 7mm SATA/NVMe kit (BU0N) with SATA drives. NVMe drives not supported. RAID is supported with the addition of the RAID 5350-8i adapter in a rear slot.
• 7mm NVMe with SFF RAID 540-8i means the 7mm SATA/NVMe kit (BU0N) with NVMe drives. SATA drives not supported. RAID is supported with the addition of the RAID 540-8i adapter in a rear slot.
• M.2 x1 SATA Non-RAID means the M.2 SATA/NVMe adapter (4Y37A09738) with SATA drives. RAID is not supported.
• M.2 x1 NVMe Non-RAID means the M.2 SATA/NVMe adapter (4Y37A09738) with NVMe drives. RAID is not supported.
• M.2 x4 SATA/NVMe Non-RAID means the M.2 SATA/x4 NVMe adapter (4Y37A79663) with either SATA or NVMe drives. RAID is not supported.
• M.2 NVMe RAID means the M.2 RAID NVMe adapter (B8P9) with NVMe drives. SATA drives not supported. RAID-0 and RAID-1 are supported with the integrated Marvell RAID controller.
• M.2 x4 SATA + RAID 5350-8i means the M.2 SATA/x4 NVMe adapter (4Y37A79663) with SATA drives. RAID is supported with the addition of the RAID 5350-8i adapter in a rear slot.
• M.2 x4 NVMe + RAID 540-8i means the M.2 SATA/x4 NVMe adapter (4Y37A79663) with NVMe drives. RAID is supported with the addition of the RAID 540-8i adapter in a rear slot.

Click to go back to the overview of 2.5-inch configurations with front slots.

When adding drive bays, you will also need to add the appropriate storage controller(s). Consult the tables in the Storage configurations section to determine what controller sections are supported and what additional controllers you will need. Controllers are described in the Controllers for internal storage section.

Upgrades to an Internal (CFF) HBA/RAID adapter

If you want to add an internal (CFF) storage adapter (HBA, RAID adapter or SAS expander) to a configuration, you will need to order the cable kit as listed in the following table. Suitable upgrades are either replacing an existing adapter in a rear PCIe slot, or adding the CFF adapter to a server without any storage adapter installed.

The cable kit to order is listed in the following table.

7mm drive bay field upgrades

For field upgrades to add 7mm drive bays, order one of the part numbers listed in the following table.

RAID flash power module (supercap) support

If you plan to add one of the RAID adapters that includes a RAID flash power module (supercap) as a field upgrade, then you will also need to order a supercap installation kit for the power module. For CTO orders, the components in the installation kit are automatically derived when you select the RAID adapter.

There are three possible locations for supercaps. Details are summarized in the following table. Location references are shown in the figure below.

The locations where supercaps are installed is shown in the following figure.

Figure 10. Location of the supercaps in the SR635 V3

When adding a RAID adapter and supercap as a field upgrade, order the supercap installation kit list listed in the following table.

The M.2 drives install into an M.2 module which is mounted horizontally in the server in front of the fans as shown in the Internal view of the server. In configurations with 2.5-inch front drive bays, the M.2 module is position between the drive bays and the fans.

The supported M.2 modules are listed in the following table. For field upgrades see the M.2 field upgrades section below.

ThinkSystem M.2 SATA/x4 NVMe 2-Bay Adapter (4Y37A79663) optionally supports RAID with the addition of a separate RAID adapter is required. For CTO orders, ordering information is listed in the following table to derive the required RAID adapter.

Configuration notes:

• M.2 is not supported with all storage configurations - see Storage configurations for details.
• For ThinkSystem M.2 SATA/NVMe 2-Bay Enablement Kit (4Y37A09738):
  • RAID is not supported
  • The installation of at least one M.2 drive is required. In the configurator, at least one M.2 drive must be selected
• For ThinkSystem M.2 SATA/x4 NVMe 2-Bay Adapter (4Y37A79663):
  • The support of RAID-1 with the M.2 drives requires an additional RAID adapter that is installed in PCIe slot 1 or 2:
    • RAID support for M.2 SATA drives requires a RAID 5350-8i adapter (feature BT7N)
    • RAID support for M.2 NVMe drives requires a RAID 540-8i adapter operating in Tri-Mode (feature BT7P)
  • The RAID adapter used for M.2 drive support cannot be configured for use with other drive bays (not even with 7mm)
  • M.2 RAID and 7mm RAID are mutually exclusive: they are not supported together in the same configuration
  • If RAID support is not required, the M.2 adapter connects to an onboard port. No additional adapter is required
  • The adapter is not supported with EDSFF drive bay configurations due to physical limitations
• For ThinkSystem M.2 NVMe 2-Bay RAID Adapter (4Y37A09750):
  • RAID is implemented using an onboard Marvell 88NR2241 NVMe RAID controller
• For ThinkSystem M.2 RAID B540i-2i SATA/NVMe Adapter (4Y37A90063):
  • RAID is implemented using an onboard Broadcom controller

M.2 field upgrades

For field upgrades, the SR635 V3 also requires additional cables necessary to connect the M.2 to either the system board or RAID adapter.

Ordering information is listed in the following table.

The IBM Security Key Lifecycle Manager software is available from Lenovo using the ordering information listed in the following table.

The SR635 V3 offers a variety of connectivity options for internal drives:

• For 2.5-inch drives:
  • Onboard SATA ports (feature AVUX)
  • Onboard NVMe ports (feature BC4V)
  • RAID adapters and HBAs for SAS/SATA drives (PCIe slot-based)
  • RAID adapters and HBAs for SAS/SATA drives (cabled in a dedicated space)
• For 7mm drive bays in the rear of the server (see the 7mm drives section)
  • SATA controller integrated into the 7mm drive bay enclosure
  • NVMe controller integrated into the 7mm drive bay enclosure
• For M.2 drives internal to the server (see M.2 drives section)
  • SATA controller integrated on the M.2 adapters
  • NVMe controller integrated on the M.2 adapters

As well as supporting RAID adapters and HBAs that install in a PCIe slot, the SR635 V3 with 2.5-inch front drive bays supports a custom form factor (CFF) adapter that is mounted in the server and cabled to one of the onboard NVMe ports.

The following table lists the adapters used for the internal storage of the server.

† Adapter also supports PCIe 4.0 x1 connectivity to NVMe drives (requires NVMe drives with U.3 interface)

Configuration notes:

• Supercap support limits the number of RAID adapters installable: The table lists whether the adapter includes a power module (supercap) to power the flash memory. The server supports 2 supercaps as described in the RAID flash power module (supercap) support section. The number of supercaps supported also determines the maximum number of RAID adapters with flash that can be installed in the server.
• Field upgrades: If you are adding a RAID adapter with supercap to the server as a field upgrade, you may need a supercap holder as described in the RAID flash power module (supercap) support section.
• 7mm drive support: The storage adapters listed in the table below do not provide connectivity to the 7mm drive bays that are optionally available at the rear of the server. The 7mm drives have their own independent RAID controller. See the Rear 2.5-inch and 7mm drive bays section for details.

• E810 Ethernet and X350 RAID/HBAs: The use of both an Intel E810 network adapter and an X350 HBA/RAID adapter (9350, 5350 and 4350) is currently not supported in ThinkSystem servers. For details see Support Tip HT513226. Planned support for this combination of adapters is 2Q/2024.

The onboard SATA controller has the following features:

• Controller integrated into the AMD processor
• JBOD only; no RAID support
• Supports up to 12 SATA drives in the SR635 V3
• Supports HDDs and SSDs; can be mixed

The onboard NVMe support has the following features:

• Controller integrated into the AMD processor
• Supports up to 16 NVMe drives direct connected to onboard ports
• Each drive has PCIe x4 host interface, up to PCIe Gen5 depending on the backplane and drive type
• Supports JBOD only - No RAID support

For specifications about the RAID adapters and HBAs supported by the SR635 V3, see the ThinkSystem RAID Adapter and HBA Reference, available from:
https://lenovopress.lenovo.com/lp1288-thinksystem-raid-adapter-and-hba-reference#sr635-v3-support=SR635%2520V3

For more information about each of the adapters, see the product guides in the RAID adapters or HBA sections of the Lenovo Press web site:
https://lenovopress.com/servers/options/raid
https://lenovopress.com/servers/options/hba

The following tables list the drive options for internal storage of the server.

The server does not supports any internal backup units, such as tape drives or RDX drives. External backup units are available as described in the External backup units section.

The server supports the external USB optical drive listed in the following table.

The drive is based on the Lenovo Slim DVD Burner DB65 drive and supports the following formats: DVD-RAM, DVD-RW, DVD+RW, DVD+R, DVD-R, DVD-ROM, DVD-R DL, CD-RW, CD-R, CD-ROM.

The SR635 V3 supports a total of up to 5x PCIe slots, 3x at the rear and 2x at the front, plus 1x OCP 3.0 SFF slot for networking. The OCP slot can be either at the front or rear. Slot availability is based on riser selection and drive bays configured.

Topics in this section:

• Rear slots
• Front slots
• Serial port

Rear slots

The following figure shows the locations of the rear-accessible and front-accessible slots for each configuration selection. The OCP slot is located below the PCIe slots.

Figure 11. SR635 V3 slot configurations

The rear-accessible slots and riser cards are as follows:

• Riser 1: Slots 1 & 2
  • Slot 1: Low Profile, PCIe x16
  • Slot 2: Low Profile or FHHL, PCIe x16 (only in configuration A, B, and E in the above figure)
• Riser 2: Slot 3
  • Slot 3: Low Profile or FHHL, PCIe x16 (only in configuration A and C)

Depending on the riser selected, the slots are either PCIe Gen4 or PCIe Gen5. Some configurations are only available with Gen4 slots.

The following table lists the configuration and ordering information for the PCIe slots in the SR635 V3. The Cfg column matches the slot configurations shown in the preceding figure. The table is divided up into configurations with Gen5 slots with Gen4, and configurations with only Gen4 slots. Ordering information is as follows:

• For CTO orders, order the feature codes listed for the configuration, both riser and cage feature codes (2 or 4 feature codes, depending on the configuration)
• For field upgrades, order the part numbers listed for the configuration (1 or 2 part numbers, depending on the configuration). The part numbers include both the risers and cages needed for that configuration.

It is also possible to build a configuration without any slots, in which case slot fillers will be derived in the configurator. Slots can be added later as field upgrades using option part numbers as listed in the Field upgrades table.

Configuration rules:

• For best performance, install PCIe 5.0 adapters in PCIe 5.0 (Gen5) slots

Front slots

As an addition or alternative to the rear slots, the SR635 V3 supports slots at the front of the server.

The following figure shows the locations of the front-accessible slots.

Figure 12. SR635 V3 front slots

The front-accessible slots and riser cards are as follows:

• Slot 4: Low Profile, PCIe 4.0 x16
• Slot 5: FHHL, PCIe 4.0 x16
• Slot 6: OCP 3.0 slot (PCIe 4.0 x16)

Ordering information is listed in the following table.

Configuration notes:

• The use of front slots requires base feature code BQ7M as described in the Base feature codes section
• Front slots can be used in conjunction with rear drive bays. See the table of configurations in the Overview - 2.5-inch front bays with front slots section for specifics.
• The front OCP slot is automatically derived by the configurator with riser 4 (slot 5)
• The front and rear OCP slots are mutually exclusive; when the front OCP slot is configured, the rear OCP slot is disconnected
• The use of the closed-loop liquid-cooled processor heatsink is not supported
• The use of the security bezel is not supported

The server has a dedicated OCP 3.0 SFF slot with PCIe 5.0 x16 host interface. See Figure 3 for the location of the OCP slot. If front slots are configured, the OCP slot is instead located at the front of the server. Only 1 OCP card can be installed in the server.

The following table lists the supported OCP adapters. One port can optionally be shared with the XCC management processor for Wake-on-LAN and NC-SI support.

The following table lists additional supported network adapters that can be installed in the regular PCIe slots.

For more information, including the transceivers and cables that each adapter supports, see the list of Lenovo Press Product Guides in the Networking adapters category:
https://lenovopress.com/servers/options/ethernet

Configuration rules:

• The following adapters are not supported installed into LP+FH riser cage (configuration B in the I/O expansion section)
  • ThinkSystem Broadcom 5719 1GbE RJ45 4-Port PCIe Ethernet Adapter, 7ZT7A00484
  • ThinkSystem I350-T4 PCIe 1Gb 4-Port RJ45 Ethernet Adapter, 7ZT7A00535
  • ThinkSystem Broadcom 57454 10GBASE-T 4-port PCIe Ethernet Adapter, 4XC7A08245

• E810 Ethernet and X350 RAID/HBAs: The use of both an Intel E810 network adapter and an X350 HBA/RAID adapter (9350, 5350 and 4350) is currently not supported in ThinkSystem servers. For details see Support Tip HT513226. Planned support for this combination of adapters is 2Q/2024.

The following table lists the Fibre Channel HBAs supported by the SR635 V3.

For more information, see the list of Lenovo Press Product Guides in the Host bus adapters category:
https://lenovopress.com/servers/options/hba

The following table lists SAS HBAs and RAID adapters supported by SR635 V3 server for use with external storage.

The SR635 V3 currently does not support any Flash storage adapters.

The SR635 V3 supports the following graphics processing units (GPUs).

* See configuration rules below

For information about these GPUs, see the ThinkSystem GPU Summary, available at:
https://lenovopress.com/lp0768-thinksystem-thinkagile-gpu-summary

Configuration rules

The following configuration requirements must be met when installing GPUs:

• All GPUs installed must be identical
• Rear drive bays bays are not supported
• Flash storage adapters are not supported.
• Maximum ambient temperature is 30°C
• Performance fans are required and will be derived by the configurator for configure-to-order builds.
• When adding GPUs as field upgrades, you will be required to replace all Standard fans with Performance fans. See the Cooling section for ordering information.

The SR635 V3 server has up to seven 40 mm dual-rotor hot-swap variable-speed fans. Five, six or seven fans are required depending on the configuration of the server. System fans are either Standard fans (21K RPM, dual-rotor) or Performance fans (28K RPM, dual-rotor), depending on the configuration. The server offers N+1 rotor redundancy.

The server also has one additional fan integrated in each of the two power supplies.

Most configurations require 6 performance fans.

The following configuration requires 7 fans:

• EDSFF drive bays + (OCP adapter or GPUs or adapter in slot 1)
• Front PCIe slots

Five fans are sufficient for the following configuration (all must apply):

• 10x 2.5-inch chassis (no front PCIe slots, no EDSFF)
• No OCP adapter
• No adapter in PCIe slot 1
• No GPUs installed
• No rear drive bays

Most configurations require performance fans. Standard fans are sufficient for the following configuration (all must apply):

• 10x 2.5-inch chassis (no front PCIe slots, no EDSFF)
• CPU < 240W TDP
• No rear drives
• No GPUs
• No networking ≥ 100GbE

For additional information, see the Thermal rules page for the SR635 V3 on the Lenovo documentation site:
http://pubs.lenovo.com/sr635-v3/thermal_rules

Ordering information for the fans is listed in the following table.

The SR635 V3 supports up to two redundant hot-swap power supplies.

The power supply choices are listed in the following table. Both power supplies used in server must be identical.

Supported power supplies are auto-sensing dual-voltage units, supporting both 110V AC (100-127V 50/60 Hz) and 220V AC (200-240V 50/60 Hz) power. For China customers, all power supplies support 240V DC. All supported AC power supplies have a C14 connector.

The supported -48V DC power supply has a Weidmuller TOP 4GS/3 7.6 terminal as shown in the following figure.

Figure 14. Connector on the ThinkSystem 1100W -48V DC Hot-Swap Gen2 Power Supply

Power supply options do not include a line cord. For server configurations, the inclusion of a power cord is model dependent. Configure-to-order models can be configured without power cords if desired.

Zero-output mode: When Zero-output mode (also known as Standby mode or Cold Redundancy mode) is configured in XCC and the server power load is sufficiently low, one of the installed power supplies enters into the Standby state while the other one delivers entire load. When the power load increases, the standby power supply will switch to Active state to provide sufficient power to the server. Zero-output mode can be enabled or disabled in the XClarity Controller web interface, Server Configuration > Power Policy. If you select Disable, then both power supplies will be in the Active state.

-48V DC power cord

For the -48V DC Power Supply, the following power cable is supported.

The SR635 V3 contains an integrated service processor, XClarity Controller 2 (XCC), which provides advanced control, monitoring, and alerting functions. The XCC2 is based on the AST2600 baseboard management controller (BMC) using a dual-core ARM Cortex A7 32-bit RISC service processor running at 1.2 GHz.

Topics in this section:

• System I/O Board
• Local management
• System status with XClarity Mobile
• Remote management
• XCC2 Platinum
• Lenovo XClarity Provisioning Manager
• Lenovo XClarity Administrator
• Lenovo XClarity Integrators
• Lenovo XClarity Essentials
• Lenovo XClarity Energy Manager
• Lenovo Capacity Planner

System I/O Board

The SR635 V3 implements a separate System I/O Board that connects to the Processor Board. The location of the System I/O Board is shown in the Components and connectors section. The System I/O Board contains all the connectors visible at the rear of the server as shown in the following figure.

Figure 15. System I/O Board

The board also has the following components:

• XClarity Controller 2, implemented using the ASPEED AST2600 baseboard management controller (BMC).
• Root of Trust (RoT) module - a daughter card that implements Platform Firmware Resiliency (PFR) hardware Root of Trust (RoT) which enables the server to be NIST SP800-193 compliant. For more details about PFR, see the Security section.
• Connector to enable an additional redundant Ethernet connection to the XCC2 controller. The connector is used in conjunction with the ThinkSystem V3 Management NIC Adapter Kit (4XC7A85319). For details, see the Remote management section.
• Internal USB port - to allow the booting of an operating system from a USB key. The VMware ESXi preloads use this port for example. Preloads are described in the Operating system support section.
• MicroSD card port to enable the use of a MicroSD card for additional storage for use with the XCC2 controller. XCC2 can use the storage as a Remote Disc on Card (RDOC) device (up to 4GB of storage). It can also be used to store firmware updates (including N-1 firmware history) for ease of deployment.

  Tip: Without a MicroSD card installed, the XCC2 controller will have 100MB of available RDOC storage.

Ordering information for the supported USB drive and Micro SD card are listed in the following table.

Configuration rules for the Pull-out operator panel:

• Only supported with configurations with 8x 2.5-inch drive bays or with EDSFF drive bays
• Not available as a field upgrade. The component is CTO or on pre-configured models only

Front VGA and External Diagnostics ports

The VGA port at the rear of the server is included in all models, however the VGA port at the front of the server is optional. The ThinkSystem V2/V3 1U Front VGA Cable Option Kit allows you to upgrade your server by adding a VGA video port to the front of the server (if the server does not already come with a front VGA port). When the front VGA is in use, the rear VGA port is automatically disabled.

The SR635 V3 optionally includes a port to connect an External Diagnostics Handset. To include in a server, ensure the appropriate feature code is included, based on the front drive configuration. Field upgrades to add the External Diagnostics port are not available.

External Diagnostics Handset

The SR635 V3 optionally includes a port to connect an External Diagnostics Handset as described in the previous section. The External Diagnostics Handset has the same functions as the Integrated Diagnostics Panel but has the advantages of not consuming space on the front of the server plus it can be shared among many servers in your data center. The handset has a magnet on the back of it to allow you to easily mount it on a convenient place on any rack cabinet.

Figure 18. External Diagnostics Handset

The following table lists the ordering information for the handset.

Information pull-out tab

The front of the server also houses an information pull-out tab (also known as the network access tag). See Figure 2 for the location. A label on the tab shows the network information (MAC address and other data) to remotely access the service processor.

The steps to connect the mobile device are as follows:

1. Enable USB Management on the server, by holding down the ID button for 3 seconds (or pressing the dedicated USB management button if one is present)
2. Connect the mobile device via a USB cable to the server's USB port with the management symbol
3. In iOS or Android settings, enable Personal Hotspot or USB Tethering
4. Launch the Lenovo XClarity Mobile app

Remote management

The server offers a dedicated RJ45 Ethernet port at the rear of the server for remote management via the XClarity Controller 2 management processor. The port supports 10/100/1000 Mbps speeds.

Remote server management is provided through industry-standard interfaces:

• Intelligent Platform Management Interface (IPMI) Version 2.0
• Simple Network Management Protocol (SNMP) Version 3 (no SET commands; no SNMP v1)
• Common Information Model (CIM-XML)
• Representational State Transfer (REST) support
• Redfish support (DMTF compliant)
• Web browser - HTML 5-based browser interface (Java and ActiveX not required) using a responsive design (content optimized for device being used - laptop, tablet, phone) with NLS support

The SR635 V3 also supports the use of an OCP adapter that provides an additional redundant Ethernet connection to the XCC2 controller. Ordering information is listed in the following table.

The use of this adapter allows concurrent remote access using both the connection on the adapter and the onboard RJ45 remote management port provided by the server. The adapter and onboard port have separate IP addresses.

Configuration rules:

• The Redundant System Management Port Adapter is installed in the OCP adapter slot at the rear of the server and is mutually exclusive with any OCP network adapter.
• It is not supported installed in the front OCP slot (if the front OCP slot is configured)
• If the Redundant System Management Port Adapter is installed in the rear slot, then the front OCP slot (if configured) cannot be used.

The following figure shows the server with the Redundant System Management Port Adapter installed in the OCP slot.

Figure 19. SR635 V3 with the Redundant System Management Port Adapter installed

XCC2 Platinum adds the following Enterprise and Advanced functions:

• Remotely viewing video with graphics resolutions up to 1600x1200 at 75 Hz with up to 23 bits per pixel, regardless of the system state
• Remotely accessing the server using the keyboard and mouse from a remote client
• International keyboard mapping support
• Syslog alerting
• Redirecting serial console via SSH
• Component replacement log (Maintenance History log)
• Access restriction (IP address blocking)
• Lenovo SED security key management
• Displaying graphics for real-time and historical power usage data and temperature
• Boot video capture and crash video capture
• Virtual console collaboration - Ability for up to 6 remote users to be log into the remote session simultaneously
• Remote console Java client
• Mapping the ISO and image files located on the local client as virtual drives for use by the server
• Mounting the remote ISO and image files via HTTPS, SFTP, CIFS, and NFS
• System utilization data and graphic view
• Single sign on with Lenovo XClarity Administrator
• Update firmware from a repository
• License for XClarity Energy Manager

Note: The SR635 V3 does not support Power capping.

With XCC2 Platinum, for CTO orders, you can request that System Guard be enabled in the factory and the first configuration snapshot be recorded. To add this to an order, select feature code listed in the following table. The selection is made in the Security tab of the DCSC configurator.

For more information about System Guard, see https://pubs.lenovo.com/xcc2/NN1ia_c_systemguard

Because Lenovo XClarity Administrator does not require any agent software to be installed on the managed endpoints, there are no CPU cycles spent on agent execution, and no memory is used, which means that up to 1GB of RAM and 1 - 2% CPU usage is saved, compared to a typical managed system where an agent is required.

Lenovo XClarity Administrator is an optional software component for the SR635 V3. The software can be downloaded and used at no charge to discover and monitor the SR635 V3 and to manage firmware upgrades.

If software support is required for Lenovo XClarity Administrator, or premium features such as configuration management and operating system deployment are required, Lenovo XClarity Pro software subscription should be ordered. Lenovo XClarity Pro is licensed on a per managed system basis, that is, each managed Lenovo system requires a license.

The following table lists the Lenovo XClarity software license options.

For more information, refer to the Lenovo XClarity Administrator Product Guide:
http://lenovopress.com/tips1200

For more information about all the available Lenovo XClarity Integrators, see the Lenovo XClarity Administrator Product Guide: https://lenovopress.com/tips1200-lenovo-xclarity-administrator

LXEM is a licensed product. A single-node LXEM license is included with the XClarity Controller Platinum upgrade as described in the XCC2 Platinum section. If your server does not have the XCC Platinum upgrade, Energy Manager licenses can be ordered as shown in the following table.

Note: The SR635 V3 does not support the following Energy Manager functions:

• Power capping
• Policy-based management

Topics in this section:

• Security features
• Platform Firmware Resiliency - Lenovo ThinkShield
• Security standards

Security features

The SR635 V3 server offers the following electronic security features:

• Secure Boot function of the AMD EPYC processor
• Support for Platform Firmware Resiliency (PFR) hardware Root of Trust (RoT) - see the Platform Firmware Resiliency section
• Firmware signature processes compliant with FIPS and NIST requirements
• System Guard (part of XCC Platinum) - Proactive monitoring of hardware inventory for unexpected component changes
• Administrator and power-on password
• Integrated Trusted Platform Module (TPM) supporting TPM 2.0
• Self-encrypting drives (SEDs) with support for enterprise key managers - see the SED encryption key management section

The server is NIST SP 800-147B compliant.

The SR635 V3 server also offers the following optional physical security features:

• Optional chassis intrusion switch
• Optional lockable front security bezel

The optional lockable front security bezel is shown in the following figure and includes a key that enables you to secure the bezel over the drives and system controls thereby reducing the chance of unauthorized or accidental access to the server.

Figure 20. Lockable front security bezel

The dimensions of the security bezel are:

• Width: 437 mm (17.2 in.)
• Height: 43 mm (1.3 in.)
• Width: 23 mm (0.9 in.)

The following table lists the physical security options for the SR635 V3.

Platform Firmware Resiliency - Lenovo ThinkShield

Lenovo's ThinkShield Security is a transparent and comprehensive approach to security that extends to all dimensions of our data center products: from development, to supply chain, and through the entire product lifecycle.

The ThinkSystem SR635 V3 includes Platform Firmware Resiliency (PFR) hardware Root of Trust (RoT) which enables the system to be NIST SP800-193 compliant. This offering further enhances key platform subsystem protections against unauthorized firmware updates and corruption, to restore firmware to an integral state, and to closely monitor firmware for possible compromise from cyber-attacks.

PFR operates upon the following server components:

• UEFI image – the low-level server firmware that connects the operating system to the server hardware
• XCC image – the management “engine” software that controls and reports on the server status separate from the server operating system
• FPGA image – the code that runs the server’s lowest level hardware controller on the motherboard

The Lenovo Platform Root of Trust Hardware performs the following three main functions:

• Detection – Measures the firmware and updates for authenticity
• Recovery – Recovers a corrupted image to a known-safe image
• Protection – Monitors the system to ensure the known-good firmware is not maliciously written

These enhanced protection capabilities are implemented using a dedicated, discrete security processor whose implementation has been rigorously validated by leading third-party security firms. Security evaluation results and design details are available for customer review – providing unprecedented transparency and assurance.

The SR635 V3 includes support for Secure Boot, a UEFI firmware security feature developed by the UEFI Consortium that ensures only immutable and signed software are loaded during the boot time. The use of Secure Boot helps prevent malicious code from being loaded and helps prevent attacks, such as the installation of rootkits. Lenovo offers the capability to enable secure boot in the factory, to ensure end-to-end protection. Alternatively, Secure Boot can be left disabled in the factory, allowing the customer to enable it themselves at a later point, if desired.

The following table lists the relevant feature code(s).

Security standards

The SR635 V3 supports the following security standards and capabilities:

• Industry Standard Security Capabilities
  • AMD CPU Enablement
    • AES-NI (Advanced Encryption Standard New Instructions)
    • GMET (Guest Mode Execute Trap)
    • Hardware-based side channel attack resilience enhancements
    • NX (No eXecute)
    • PSB (Platform Secure Boot)
    • Shadow Stack
    • SEV (Secure Encrypted Virtualization)
    • SEV-ES (Encrypted State register encryption)
    • SEV-SNP (Secure Nested Paging)
    • SVM (Secure Virtual Machine)
    • SME (Secure Memory Encryption)
    • UMIP (User Mode Instruction Prevention)
  • Microsoft Windows Security Enablement
    • Credential Guard
    • Device Guard
    • Host Guardian Service
  • TCG (Trusted Computing Group) TPM (Trusted Platform Module) 2.0
  • UEFI (Unified Extensible Firmware Interface) Forum Secure Boot
• Hardware Root of Trust and Security
  • Independent security subsystem providing platform-wide NIST SP800-193 compliant Platform Firmware Resilience (PFR)
  • Host domain RoT supplemented by AMD Platform Secure Boot (PSB)
  • Management domain RoT supplemented by the Secure Boot features of XCC
• Platform Security
  • Boot and run-time firmware integrity monitoring with rollback to known-good firmware (e.g., “self-healing”)
  • Non-volatile storage bus security monitoring and filtering
  • Resilient firmware implementation, such as to detect and defeat unauthorized flash writes or SMM (System Management Mode) memory incursions
  • Patented IPMI KCS channel privileged access authorization (USPTO Patent# 11,256,810)
  • Host and management domain authorization, including integration with CyberArk for enterprise password management
  • KMIP (Key Management Interoperability Protocol) compliant, including support for IBM SKLM and Thales KeySecure
  • Reduced “out of box” attack surface
  • Configurable network services
  • FIPS 140-3 (in progress) validated cryptography for XCC
  • CNSA Suite 1.0 Quantum-resistant cryptography for XCC
  • Lenovo System Guard

  For more information on platform security, see the paper “How to Harden the Security of your ThinkSystem Server and Management Applications” available from https://lenovopress.com/lp1260-how-to-harden-the-security-of-your-thinksystem-server.

• Standards Compliance and/or Support
  • NIST SP800-131A rev 2 “Transitioning the Use of Cryptographic Algorithms and Key Lengths”
  • NIST SP800-147B “BIOS Protection Guidelines for Servers”
  • NIST SP800-193 “Platform Firmware Resiliency Guidelines”
  • ISO/IEC 11889 “Trusted Platform Module Library”
  • Common Criteria TCG Protection Profile for “PC Client Specific TPM 2.0”
  • European Union Commission Regulation 2019/424 (“ErP Lot 9”) “Ecodesign Requirements for Servers and Data Storage Products” Secure Data Deletion
  • Optional FIPS 140-2 validated Self-Encrypting Disks (SEDs) with external KMIP-based key management
• Product and Supply Chain Security
  • Suppliers validated through Lenovo’s Trusted Supplier Program
  • Developed in accordance with Lenovo’s Secure Development Lifecycle (LSDL)
  • Continuous firmware security validation through automated testing, including static code analysis, dynamic network and web vulnerability testing, software composition analysis, and subsystem-specific testing, such as UEFI security configuration validation
  • Ongoing security reviews by US-based security experts, with attestation letters available from our third-party security partners
  • Digitally signed firmware, stored and built on US-based infrastructure and signed on US-based Hardware Security Modules (HSMs)
  • TAA (Trade Agreements Act) compliant manufacturing, by default in Mexico for North American markets with additional US and EU manufacturing options
  • US 2019 NDAA (National Defense Authorization Act) Section 889 compliant

The following table lists the rack installation options that are available for the SR635 V3.

The following table summarizes the rail kit features and specifications.

* CMA mounting brackets are not preinstalled on the rail. The CMA mounting brackets are contained in the CMA option kit package and you will need to install the CMA mounting brackets first. For detailed instructions, refer to the documentation that comes with the CMA option kit.
** If you want to install the rails and a 0U PDU into the same rack, the rack must meet the height and depth requirements as described in ThinkSystem Rail Support Matrix.
‡ For best performance, it is recommended that you install the rails to the racks with a 719-mm distance (28.31-inch, Lenovo rack default distance) between the front and rear mounting flanges.
† Measured when mounted on the rack, from the front surface of the front mounting flange to the rear most point of the rail. Rail is in closed position.

The SR635 V3 supports the following operating systems:

• Microsoft Windows 10 Professional (x64)
• Microsoft Windows 11 Professional (x64)
• Microsoft Windows Server 2019
• Microsoft Windows Server 2022
• Red Hat Enterprise Linux 8.6
• Red Hat Enterprise Linux 8.7
• Red Hat Enterprise Linux 8.8
• Red Hat Enterprise Linux 8.9
• Red Hat Enterprise Linux 9.0
• Red Hat Enterprise Linux 9.1
• Red Hat Enterprise Linux 9.2
• Red Hat Enterprise Linux 9.3
• SUSE Linux Enterprise Server 15 SP4
• SUSE Linux Enterprise Server 15 SP5
• SUSE Linux Enterprise Server 15 Xen SP4
• SUSE Linux Enterprise Server 15 Xen SP5
• Ubuntu 20.04 LTS 64-bit
• Ubuntu 22.04 LTS 64-bit
• VMware ESXi 7.0 U3
• VMware ESXi 8.0
• VMware ESXi 8.0 U1
• VMware ESXi 8.0 U2

For a complete list of supported, certified and tested operating systems, plus additional details and links to relevant web sites, see the Operating System Interoperability Guide: https://lenovopress.lenovo.com/osig#servers=sr635-v3-7d9g&support=all

For configure-to-order configurations, the server can be preloaded with VMware ESXi installed on M.2 cards. Ordering information is listed in the following table.

Configuration rule:

• An ESXi preload cannot be selected if the configuration includes an NVIDIA GPU (ESXi preload cannot include the NVIDIA driver)

You can download supported VMware vSphere hypervisor images from the following web page and load it on the M.2 drives or 7mm drives using the instructions provided:
https://vmware.lenovo.com/content/custom_iso/

Windows 10 and Windows 11

The SR635 V3 can now run Windows 10 and Windows 11, however only a subset of adapters and drives can be installed. For ease of configuration, additional Base CTO models 7D9GCTO2WW and 7D9HCTO2WW have been created to assist building a configuration that can be used with the client operating systems. See the Models section for details.

The XClarity management toolset is supported with Windows 10 and Windows 11.

See the part number tables in the following sections to see which adapters are supported with Windows 10 and Windows 11:

• Controllers for internal storage
• M.2 adapters
• Network adapters
• GPU adapters

The following components are not supported:

• Fibre Channel adapters
• InfiniBand and VPI adapters
• External storage adapters
• Flash storage adapters

The SR635 V3 has the following overall physical dimensions, excluding components that extend outside the standard chassis, such as EIA flanges, front security bezel (if any), and power supply handles:

• Width: 440 mm (17.3 inches)
• Height: 43 mm (1.7 inches)
• Depth: 773 mm (30.4 inches)

The following table lists the detailed dimensions. See the figure below for the definition of each dimension.

Figure 21. Server dimensions

The server has the following weight:

• Maximum weight: 20.2 kg (44.6 lb)

The server has the following electrical specifications for AC input power supplies:

• Input voltage:
  • 100 to 127 (nominal) Vac, 50 Hz or 60 Hz
  • 200 to 240 (nominal) Vac, 50 Hz or 60 Hz
  • 180 to 300 Vdc (China only)
• Inlet current: see the following table.

Electrical specifications for DC input power supply:

• Input voltage: -48 to -60 Vdc
• Inlet current (1100W power supply): 26 A

The SR635 V3 server complies with ASHRAE Class A2 specifications with most configurations, and depending on the hardware configuration, also complies with ASHRAE Class A3 and Class A4 specifications. System performance may be impacted when operating temperature is outside ASHRAE A2 specification.

Depending on the hardware configuration, the SR635 V3 server also complies with ASHRAE Class H1 specification. System performance may be impacted when operating temperature is outside ASHRAE H1 specification.

Topics in this section:

• Ambient temperature requirements
• Temperature and humidity
• Heat output
• Acoustical noise emissions
• Shock and vibration
• Particulate contamination

Ambient temperature requirements

The restrictions to ASHRAE support are as follows:

• The ambient temperature must be limited to 45°C or lower (TDP ＜ 240W) if the server meets the following conditions:
  • Installed with any TruDDR5 memory DIMM (64 GB or below)
  • Without 2.5" NVMe, NVMe M.2 or NVMe AIC drives
  • Without rear drives or 7mm drives
  • Without GPU adapters
  • Without any PCIe network interface cards (NICs) at a rate ≥ 25 GB
  • Without any parts with AOC and at a rate ≥ 25 GB
  • Without closed loop heat sink
• The ambient temperature must be limited to 40°C or lower (TDP ＜300 W) if the server meets the following conditions:
  • Installed with any TruDDR5 memory DIMM (64 GB or below)
  • Without 2.5" NVMe, NVMe M.2 or NVMe AIC drives
  • Without rear drives or 7mm drives
  • Without GPU adapters
  • Without any PCIe network interface cards (NICs) at a rate ≥ 25 GB
  • Without any parts with AOC and at a rate ≥ 25 GB
  • Without closed loop heat sink
• The ambient temperature must be limited to 35°C or lower (320 W ≤TDP ≤ 400 W) if the server has any of the following components:
  • TruDDR5 memory 128 GB DIMM
  • ThinkSystem 256GB TruDDR5 4800MHz (8Rx4) 3DS RDIMM-A v2
  • NVMe, NVMe M.2 or NVMe AIC drives
  • Broadcom 57416 10GBASE-T 2-port OCP
  • Broadcom 57454 10GBASE-T 4-port OCP
  • PCIe network interface cards (NICs) at a rate of 25 GB
  • Parts with AOC and at a rate of 25 GB
  • GPU adapters
• The ambient temperature must be limited to 30°C or lower if the server has any of the following components:
  • Rear drives
  • EDSFF drives
  • Parts with AOC and at a rate > 25 GB
  • PCIe network interface cards (NICs) at a rate > 25 GB

For additional information, see the Environmental specifications and Thermal rules sections in the product documentation:
https://pubs.lenovo.com/sr635-v3/server_specifications_environmental
https://pubs.lenovo.com/sr635-v3/thermal_rules

Temperature and humidity

The server is supported in the following environment:

• Air temperature:
  • Operating:
    • ASHRAE Class A2: 10°C to 35°C (50°F to 95°F); the maximum ambient temperature decreases by 1°C for every 300 m (984 ft) increase in altitude above 900 m (2,953 ft).
    • ASHRAE Class A3: 5°C to 40°C (41°F to 104°F); the maximum ambient temperature decreases by 1°C for every 175 m (574 ft) increase in altitude above 900 m (2,953 ft).
    • ASHRAE Class A4: 5°C to 45°C (41°F to 113°F); the maximum ambient temperature decreases by 1°C for every 125 m (410 ft) increase in altitude above 900 m (2,953 ft).
    • ASHRAE Class H1: 5 °C to 25 °C (41 °F to 77 °F); Decrease the maximum ambient temperature by 1°C for every 500 m (1640 ft) increase in altitude above 900 m (2,953 ft).
  • Server off: 5°C to 45°C (41°F to 113°F)
  • Shipment/storage: -40°C to 60°C (-40°F to 140°F)
• Maximum altitude: 3,050 m (10,000 ft)
• Relative Humidity (non-condensing):
  • Operating
    • ASHRAE Class A2: 8% to 80%; maximum dew point: 21°C (70°F)
    • ASHRAE Class A3: 8% to 85%; maximum dew point: 24°C (75°F)
    • ASHRAE Class A4: 8% to 90%; maximum dew point: 24°C (75°F)
    • ASHRAE Class H1: 8% to 80%; Maximum dew point: 17°C (63°F)
  • Shipment/storage: 8% to 90% 

Acoustical noise emissions

The SR635 V3 has the following acoustic noise emissions declaration:

• Sound power level (L_WAd):
  • Idling: 6.7 Bel (Typical), 6.7 Bel (GPU rich), 7.4 Bel (Storage rich)
  • Operating: 8.4 Bel (Typical), 8.3 Bel (GPU rich), 7.9 Bel (Storage rich)

• Sound pressure level (L_pAm):
  • Idling: 52.3 dBA (Typical), 52.3 dBA (GPU rich), 59.9 dBA (Storage rich)
  • Operating: 68.7 dBA (Typical), 67.7 dBA (GPU rich), 64.1 dBA (Storage rich)

Notes:

• These sound levels were measured in controlled acoustical environments according to procedures specified by ISO7779 and are reported in accordance with ISO 9296.
• The declared acoustic sound levels are based on the following configurations, which may change depending on configuration/conditions：
  • Typical: 1x 300W CPU, 12x 64GB RDIMM, 10x SAS HDD, 440-16i CFF raid, Broadcom 5719 1GbE RJ45 4-port OCP Ethernet Adapter, 2x 1100W PSU
  • GPU rich: 1x 300W CPU, 12x 64GB RDIMM, 10x SAS HDD, 440-16i CFF raid, Broadcom 5719 1GbE RJ45 4-port OCP Ethernet Adapter, 1x A2 GPU, 2x 1100W PSU
  • Storage rich: 1x 240W CPU, 12x 64GB RDIMM, 12x SAS HDD, 440-16i CFF raid, Broadcom 5719 1GbE RJ45 4-port OCP Ethernet Adapter, 2x 750W PSU

Government regulations (such as those prescribed by OSHA or European Community Directives) may govern noise level exposure in the workplace and may apply to you and your server installation. The actual sound pressure levels in your installation depend upon a variety of factors, including the number of racks in the installation; the size, materials, and configuration of the room; the noise levels from other equipment; the room ambient temperature, and employee's location in relation to the equipment. Further, compliance with such government regulations depends on a variety of additional factors, including the duration of employees' exposure and whether employees wear hearing protection. Lenovo recommends that you consult with qualified experts in this field to determine whether you are in compliance with the applicable regulations.