Ok I think i've pretty much figured out the culprit..
I disabled the PCI-e power savings setting in Windows 11, and re-enabled/installed all AMD drivers I got rid off. It seems that I was getting good speed until a few minutes after startup since Windows was dynamically activating it's power savings on the CX-3. I have a GTX1080 in the bottom x4 Chipset slot.
I get ~39gbps via ntttcp (~26 with iperf3) until I open Firefox, it seems opening Firefox or doing anything which makes use of the GPU slows down the connection to ~14gbps both on iperf and ntttcp.
This makes sense as the file server ( the system that's behaving perfectly) has no dedicated GPU or any other PCI-e devices for that matter.
I suspect the GPU is drawing more power via the PCIe lanes and the power management is throttling the CX-3 hence the slower speed when firefox is opened.
I disabled the PCI-e power savings setting in Windows 11, and re-enabled/installed all AMD drivers I got rid off. It seems that I was getting good speed until a few minutes after startup since Windows was dynamically activating it's power savings on the CX-3. I have a GTX1080 in the bottom x4 Chipset slot.
I get ~39gbps via ntttcp (~26 with iperf3) until I open Firefox, it seems opening Firefox or doing anything which makes use of the GPU slows down the connection to ~14gbps both on iperf and ntttcp.
This makes sense as the file server ( the system that's behaving perfectly) has no dedicated GPU or any other PCI-e devices for that matter.
I suspect the GPU is drawing more power via the PCIe lanes and the power management is throttling the CX-3 hence the slower speed when firefox is opened.
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