Created attachment 301277 [details] Journal: Attachment-A My PowerColor Radeon Rx 6400 ITX never works. I explain it step by step. My regular hardware set is here and it surely works well, CPU: Ryzen 3 PRO 4350G MB: Asrock A520M-ITX/AC BIOS: v1.90 Display output: From Ryzen 3 PRO 4350G via HDMI. Next, I turn off the power supply and add Radeon RX 6400 and output from RX 6400. In this time, a mosaic screen is shown. After some seconds, the screen becomes black out. Neither CTRL-ALT-DEL nor SysRq keys are work. (Attachment-A is the journal of this run)
Created attachment 301278 [details] Journal: Attachment-B
Created attachment 301279 [details] Journal: attachment-C
Next, I add the Rx 6400 and change display output via Ryzen 3 PRO 4350G. The run goes to reboot automatically. The journal is Attachment-B. Finally, the run after the automatic reboot works. The journal is attachment-C.
Created attachment 301280 [details] .config for my kernel build.
Does adding amdgpu.runpm=0 to the kernel command line in grub help?
Created attachment 301293 [details] journal with rx6400 and amdgpu.runpm=0
Comment on attachment 301293 [details] journal with rx6400 and amdgpu.runpm=0 I put RX 6400 and output from RX 6400. It crashed and I could not do soft reset. Thus, I turned off the power supply.
Created attachment 301294 [details] Journal with 4350G and amdgpu.runpm=0 Next, I change my output from RX 6400 to Ryzen 4350G. It frozen after boot. I could not do soft reset. Thus, I turned off the power supply.
Created attachment 301295 [details] journal with 4350G and amdgpu.runpm=0, 2nd boot. Next, I kept the hardware setting (RX 6400 was still on but output from Ryzen 4350G) and boot. This is the journal.
Does setting amdgpu.aspm=0 on the kernel command line help?
Created attachment 301305 [details] journal with amdgpu.aspm=0 Adding amdgpu.aspm=0 makes my Rx 6400 work fine. Thank you.