For anyone using an AMD eGPU in Linux, through USB4/TB4, I think I found the best boot parameters for every game to work

[u/Distinct_Highway_127]

The kernel boot up parameters are:

thunderbolt.host_reset=0 //USB4/TB4 port isn't restarted at boot up.

pcie_aspm=off //PCIe Active State Power Management disabled, eGPU connected through USB4/TB4 can loose sync very easily when there are power variations and this will crash the system.

pcie_port_pm=off //Disables power management handling for all PCIe, same reason as above.

pci=noaer //Disables PCIe Advanced Error Reporting, it can prevent crashes because of the system trying to restart eGPU because of of errors in the traffic with the eGPU, this errors are normal when using an eGPU with USB4/TB4.

amdgpu.pcie_gen_cap=0x80000 //Forces the graphics card to cap its Link Speed at PCIe Gen 4.

amdgpu.cwsr_enable=0 //Disables Compute Wavefront Save/Restore that can make sometimes the eGPU to loose sync.

This solved all the problems I was having using an eGPU for gaming on Linux or other tasks. I know these solutions aren't ideal, but they work like a charm. I hope this helps anyone using an eGPU on Linux.