I bought the network card and plugged it in, but found that it could not negotiate 100G, or the dual-port 25G only ran to half the bandwidth. It was probably because the speed gear and the PCIe channel were not aligned. Selecting a network card is not an isolated action, it must be checked together with the switch port and slot bandwidth.

Identify the gear first and then talk about adaptation

Common gears are 10G, 25G, 40G, and 100G. Optical port type and speed binding: 10G uses SFP+, 25G uses SFP28, 40G uses QSFP+, and 100G uses QSFP28. E810 generation ports usually support 25G and 10G, 100G and 40G downward adaptation, while 82599 and X550 do not support 25G. New cards on old switch ports may also be speed-limited, such asPCI-EX16 100G single optical port fiber optic network card (Intel E810 chip)If plugged into a switch with only 10G ports, it can only run 10G.

The number of PCIe lanes determines the performance limit of the card

  • 10 Gigabit single port: PCIe 3.0 x4 is enough.
  • 25G dual port: Generally requires x8 slot, and the throughput of x4 slot is directly halved.
  • 40G dual port total 80G: x16 required, referencePCI-EX8 40G dual optical port fiber optic network card (Intel XL710 chip)Slot requirements for this type of card.
  • 100G single port: usually requires PCIe 4.0/5.0 x16. Check the motherboard manual to confirm the slot generation before installation.

Checklist for targeting by traffic

For ordinary Web and office virtualization, dual-port 10G is still cost-effective; for distributed storage and medium-scale virtualization, it is recommended to start at 25G; for AI training, large model data loading and core aggregation, 100G can be used directly. When setting the schedule, look at the switch side port density and budget simultaneously. It is usually unrealistic to fully upgrade the access layer to 100G.Data center high-speed interconnection solutionThe approach here is to use 25G for business access and 100G for storage and GPU. First calculate the actual traffic of each server and then decide on the level. EB-LINK's network cards and modules are tested one by one according to the port speed before shipment. If you are not sure about the speed, please dial 0755-83179002 to check.