Configuring 200Gb and 400Gb Link Speeds on the Broadcom 57608 Ethernet Adapters

The ThinkSystem Broadcom 57608 2x200/1x400GbE QSFP112 Ethernet Adapters are high-performance dual-port 200Gb Ethernet adapters with a PCIe 5.0 x16 host interface that are designed to build highly scalable, feature-rich networking solutions in servers for AI/ML, cloud, high-performance computing, and storage applications.

For technical information about the adapter including server and operating system support, see the Lenovo Press product guide.

Figure 1. ThinkSystem Broadcom 57608 2x200/1x400GbE QSFP112 Ethernet Adapter

This document guide how to configure the 200Gb and 400Gb speeds for the adapter. The adapter supports 2 modes:

• 2x 200Gb ports
• 1x 400Gb port

The 2x 200Gb mode is the default. To change the mode, the user will need to manually set the relevant configuration under the UEFI System Setup.

The BCM957608 network adapter is configured by default to auto-negotiate and auto detect the appropriate speed of the switch port and ensure a proper link:

• Speeds up to 200G – No additional configuration is required. The BCM957608 (single or dual-port) is configured by default to link up at the maximum speed supported by the switch, up to 200G.
• 400G speeds – The BCM957608 dual-port Ethernet adapter can be converted to single-port adapter and automatically detect the speed up to 400G. The Port Operation Mode setting must be manually configured.

Other configurations can be manually set using the information in the following sections.

By default, the BCM957608 dual-port is automatically configured for 200G speeds. This section provides information on configuring the adapter to force 200G PAM-4 link speeds as an example. It is also possible to configure 200G PAM-4-112, 400G PAM4, 400G PAM-4-112, and other supported speeds.

The steps in the UEFI System Setup are as follows:

1. Boot system to the F1 UEFI setup
2. Go to System Settings > Network > AUT > Device Configuration Menu.
3. Ensure the Port Operation Mode parameter is set to Physical Port Configuration as the default value.

   
   Figure 1. Port Operation Mode setting

4. Go to System settings > Network > AUT > Link Configuration.
5. Set the Operational Link Speed parameter to 200Gbps PAM4.

   
   Figure 2. Operational Link Speed setting

6. The next step is to set the Port Link Training parameter, based on the link cable type you are using. The default is Enabled.

   
   Figure 3. Port Link Training setting

   Configure Port Link Training when using forced link speed. Link training should be enabled when using DAC cables in PAM4 mode and link training should be disabled when using AOC/Optical modules. See the table for the correct setting for each cable type.

   Table 1. Link Training Configuration setting based on cable type

   Cable Type	Link Training Enable/Disable
   Passive Direct Attach Copper (DAC)	Link Training - Enable
   Active Direct Attach Copper (DAC)	Link Training - Disable
   Active Optical cable (AOC)	Link Training - Disable
   Active Copper Cable (ACC)	Link Training - Disable

   Tip: The setting of "Link Training" as enabled or disabled depends on both the modules and the switches. The guidance you get is just a general idea, not the way you have to follow. It is also not related to PAM4 or not.

   When you have a passive cable which usually is DAC, then you need to enable Link training no matter whether it is forced or auto speed.

   With active cables, you need to disable Link Training as the module will do the link signal integrity without relying on the NIC firmware when the auto is not used.

7. Save the changes in UEFI and reboot the system to take effect.

This section provides information for configuration 400G link speeds using Port Operation Mode as Disable port 2.

The steps in the UEFI System Setup are as follows:

1. Boot system to the F1 UEFI setup.
2. Go to System Settings > Network > AUT > Device Configuration Menu.
3. Set the Port Operation Mode parameter to Disable port 2

   
   Figure 4. Port Operation Mode setting

4. Reboot the server for this change to take effect

This section provides information on configuring the adapter to force 400G PAM-4 link speeds as an example. It is also possible to configure 200G PAM-4-112, 400G PAM4, 400G PAM-4-112, and other supported speeds.

The steps in the UEFI System Setup are as follows:

1. Boot system to the F1 UEFI setup
2. Go to System Settings > Network > AUT > Device Configuration Menu.
3. Set the Port Operation Mode parameter to Disable port 2.

   
   Figure 5. Port Operation Mode setting

4. Go to System Settings > Network > AUT > Link Configuration.
5. Set the Operational Link Speed parameter to 400Gbps PAM4-112.

   
   Figure 6. Operational Link Speed setting

6. Set the Port Link Training parameter based on the link cable type. The default is Enabled.

   
   Figure 7. Port Link Training setting

   Configure Port Link Training when using forced link speed. Link training should be enabled when using DAC cables in PAM4 mode and link training should be disabled when using AOC/Optical modules. See the table for the correct setting for each cable type.

   Table 2. Link Training Configuration per Cable Type

   Cable Type	Link Training Enable/Disable
   Passive Direct Attach Copper (DAC)	Link Training - Enable
   Active Direct Attach Copper (DAC)	Link Training - Disable
   Active Optical cable (AOC)	Link Training - Disable
   Active Copper Cable (ACC)	Link Training - Disable

   Tip: The setting of "Link Training" as enabled or disabled depends on both the modules and the switches. The guidance you get is just a general idea, not the way you have to follow. It is also not related to PAM4 or not.

   When you have a passive cable which usually is DAC, then you need to enable Link training no matter it is forced or auto speed.

   With active cables, you need to disable Link Training as the module will do the link signal integrity without relying on the NIC firmware when the auto is not used.

7. Save the changes in UEFI and reboot the system to take effect. 

For more information, see the following resource:

• ThinkSystem Broadcom 57608 2x200/1x400GbE QSFP112 Ethernet Adapter product guide:
  https://lenovopress.lenovo.com/lp2013-thinksystem-broadcom-57608-2x200-1x400gbe-qsfp112-ethernet-adapters

Hongqiao Du is a Lenovo Senior Engineer responsible for Broadcom Ethernet adapters in Lenovo ThinkSystem servers. Hongqiao has worked in the IT industry since 2022, and is currently based in Tianjinn, China. Hongqiao holds a Master’s Degree in Engineering from Yanshan University.