Asus XG-C100C speed degrades after a few hours to 150Mbps

Hey Guys,

so I am trying to troubleshoot issues with two Asus XG-C100C cards that simply will not behave like they should.
I’ve optimized settings for max throughput but the bw does not stay. After a few hours network speed degrades down from ~7Gbps to about 150-250 Mbps.

  • Unplugging and replugging the cable does not help
  • Restarting the switch does not help
  • Disabling/Enabeling the card in Windows Device Manager restores speed for a few hours

Only one of the systems seems to be affected since restarting the device on the other PC does not change anything.


  • Updated drivers
  • placed a dedicated cooling fan at the heatsink
  • replaced all cables
  • tried direct connection as well
  • swapped the card to a different PCIe X16 (electronical) slot

I am out of options by now…

Have you guys any idea what could be happening here?