I’ve been running a Ubuntu 18.04 system for a while with an old single slot AMD Radeon HD 7750 (cape verde) gpu. The tiny single slot is necessary as it’s crammed in among other PCIe devices. I recently tried to connect a 3rd monitor and no luck. Apparently it requires active display adapters for anything more than 2 displays. I have dozens of display adapters, none active. Rather than spend $30 on yet another display adapter I figured I’ll just get the cheapest single slot GPU of a more current architecture. The HD 7750 occasionally has issues with random stuff due to being ancient (like more than 2 displays), I figure 8yrs of use is good enough.
Enter the Radeon Pro WX 2100 from ebay for $40.
I figured, I already have the driver installed, should be plug and play. Oh how naive. Won’t boot, I get a kernel panic. Of course it’s never that easy.
Booted to a windows disk just for sanity check, booted right up with the WX 2100, recognized it and had no issues. So gpu works.
Tried to boot to a Ubuntu 18.04.5 live USB with the WX 2100 in the system. Nope. Won’t boot. Flashes “AMD-VI completion wait loop” and then just sits at a blank purple ubuntu screen forever. To me, this makes no sense. The Live USB should have worked. I thought maybe some boot flags in grub on the system drive may have messed things up but they shouldn’t impact the live USB at all, right?
I know theres something weird about AMD gpu drivers for linux, theres Radeon drivers vs AMDGPU drivers? I don’t totally understand the difference.
Looks like i am using the “Radeon” drivers.
Is this the correct procedure?
-Boot to a live USB with the old gpu installed
-delete the drivers from the system disk?
-Install new gpu, boot to live USB
-install new drivers to system disk?
asrock b450m pro4 (bios v4.20 AMD AGESA Combo-AM4 PI 18.104.22.168)
ryzen 9 3900x
wd sn750 pcie boot drive
radeon hd 7750 / Radeon pro wx 2100
Only noteworthy quirk I can think of is the gpu is installed in a chipset pcie 2.0 slot, all cpu pcie 3.0 slots are occupied with nvme drives. The HD 7750 didn’t seem to care one bit.