How can I modify the bandwidth or latency of PCIe, or at least be able to change the bandwidth

Due to the need to downclock the GPU, I am looking to modify the PCIe bandwidth and latency, or at least one of these aspects. One method I’ve considered is altering the configurations within /sys/bus/pci/devices/ to disable some lanes of the same PCIe connection (note, it’s about partial lanes of the same PCIe), thereby adjusting the PCIe bandwidth. Since it’s a server’s Linux system, I would prefer not to make changes to the BIOS. I hope to receive some guidance or assistance on this matter. Thank you in advance for your help.

There is no way publically available way to change PCIe generation outside of performance states. To force a performance state, use

nvidia-smi --lock-memory-clocks=<clockMin, clockMax>

Thank you very much for being willing to offer help. I would like to reduce the bandwidth by disabling some PCIe lanes, and I’m wondering if you are familiar with this part.

Using your motherboard’s BIOS would be the only real way. I’m sure Nvidia has some working debug functions to change PCIe width/speed but they are very stingy with API access.

Thank you very much for being willing to offer help. Recently, I discovered a command called setpci and am currently studying it, hoping it can contribute some assistance to this issue.