X470D4U/p4.20/Ryzen5600G 'fatal error' @ GPU boot

Hello, i also had some issues, but after spending...a lot of time searching and trying, i found a solution for myself.

the issue for me was the CSM legacy layer causing issue, UEFI mod only worked.
i'm usinf bios 4.24 beta

in BIOS

boot option filter "UEFI only"

CSM (compatibility support module) "Custom" other and video both change to UEFI only

now restart

my unraid booted up with the GPU working, and all the errors before about reading bios rom and things are gone.

@Registered55 amazing, it looks like it works! Thanks so much for finding and sharing this.

@amissus see post above ^.

ls -l /dev/dri
total 0
drwxr-xr-x 2 root root        100 Mar 24 02:50 by-path
crw-rw---- 1 root video 226,   0 Mar 24 02:50 card0
crw-rw---- 1 root video 226,   1 Mar 24 02:50 card1
crw-rw-rw- 1 root render 226, 128 Mar 24 02:50 renderD128

inxi -FZ | grep -A4 'Graphics:'
Graphics:
Device-1: ASPEED Graphics Family driver: ast v: kernel
Device-2: AMD Cezanne driver: amdgpu v: kernel
Display: server: No display server data found. Headless machine? tty: 160x40
Message: GL data unavailable in console for root.

Mar 24 02:50:10 server kernel: [drm] amdgpu kernel modesetting enabled.
Mar 24 02:50:10 server kernel: vga_switcheroo: detected switching method \_SB_.PCI0.GP17.VGA_.ATPX handle
Mar 24 02:50:10 server kernel: ATPX version 1, functions 0x00000000
Mar 24 02:50:10 server systemd-networkd[2501]: Enumeration completed
Mar 24 02:50:10 server systemd[1]: Started Network Configuration.
Mar 24 02:50:10 server audit[1]: SERVICE_START pid=1 uid=0 auid=4294967295 ses=4294967295 msg='unit=systemd-networkd comm="systemd" exe="/usr/lib/systemd/syste>
Mar 24 02:50:10 server kernel: amdgpu: Virtual CRAT table created for CPU
Mar 24 02:50:10 server kernel: amdgpu: Topology: Add CPU node
Mar 24 02:50:10 server kernel: [drm] initializing kernel modesetting (RENOIR 0x1002:0x1638 0x1002:0x1636 0xD8).
Mar 24 02:50:10 server kernel: amdgpu 0000:30:00.0: amdgpu: Trusted Memory Zone (TMZ) feature enabled
Mar 24 02:50:10 server kernel: [drm] register mmio base: 0xFCD00000
Mar 24 02:50:10 server kernel: [drm] register mmio size: 524288
Mar 24 02:50:10 server kernel: [drm] add ip block number 0 <soc15_common>
Mar 24 02:50:10 server kernel: [drm] add ip block number 1 <gmc_v9_0>
Mar 24 02:50:10 server kernel: [drm] add ip block number 2 <vega10_ih>
Mar 24 02:50:10 server kernel: [drm] add ip block number 3 <psp>
Mar 24 02:50:10 server kernel: [drm] add ip block number 4 <smu>
Mar 24 02:50:10 server kernel: [drm] add ip block number 5 <dm>
Mar 24 02:50:10 server kernel: [drm] add ip block number 6 <gfx_v9_0>
Mar 24 02:50:10 server kernel: [drm] add ip block number 7 <sdma_v4_0>
Mar 24 02:50:10 server kernel: [drm] add ip block number 8 <vcn_v2_0>
Mar 24 02:50:10 server kernel: [drm] add ip block number 9 <jpeg_v2_0>
Mar 24 02:50:10 server kernel: amdgpu 0000:30:00.0: amdgpu: Fetched VBIOS from VFCT
Mar 24 02:50:10 server kernel: amdgpu: ATOM BIOS: 113-CEZANNE-018
Mar 24 02:50:10 server kernel: [drm] VCN decode is enabled in VM mode
Mar 24 02:50:10 server kernel: [drm] VCN encode is enabled in VM mode
Mar 24 02:50:10 server kernel: [drm] JPEG decode is enabled in VM mode
Mar 24 02:50:10 server kernel: amdgpu 0000:30:00.0: amdgpu: PCIE atomic ops is not supported
Mar 24 02:50:10 server kernel: [drm] vm size is 262144 GB, 4 levels, block size is 9-bit, fragment size is 9-bit
Mar 24 02:50:10 server kernel: amdgpu 0000:30:00.0: amdgpu: VRAM: 512M 0x000000F400000000 - 0x000000F41FFFFFFF (512M used)
Mar 24 02:50:10 server kernel: amdgpu 0000:30:00.0: amdgpu: GART: 1024M 0x0000000000000000 - 0x000000003FFFFFFF
Mar 24 02:50:10 server kernel: amdgpu 0000:30:00.0: amdgpu: AGP: 267419648M 0x000000F800000000 - 0x0000FFFFFFFFFFFF
Mar 24 02:50:10 server kernel: [drm] Detected VRAM RAM=512M, BAR=512M
Mar 24 02:50:10 server kernel: [drm] RAM width 128bits DDR4
Mar 24 02:50:10 server kernel: [drm] amdgpu: 512M of VRAM memory ready
Mar 24 02:50:10 server kernel: [drm] amdgpu: 3072M of GTT memory ready.
Mar 24 02:50:10 server kernel: [drm] Found VCN firmware Version ENC: 1.16 DEC: 5 VEP: 0 Revision: 3
Mar 24 02:50:10 server kernel: amdgpu 0000:30:00.0: amdgpu: Will use PSP to load VCN firmware

Regarding the tip from registered55
When CSM is disabled, the graphics card MUST support Graphics Output Protocol (GOP) and a 710 card definitely does not support GOP.
On a dekstop board, it means that the system will go back into BIOS.
The only way to solve this, is to enable CSm, set launch Storage OpROM Policy to UEFI only, and launch Video OpROM Policy, to Legacy.
This way the card will work in legacy mode, while the OS can run in UEFI mode.
With a card that does support GOP, UEFI assumes, the card supports certain standards, and initialize it, using that standard.
So there is a difference between the handling of Legacy hardware versus GOP supported hardware.
On newer boards, it can be that Intel/AMD no longer support legacy hardware

I would like to thank @Registered55 for the solution.

I had the similar issue with X470D4U, Ryzen 5700G, and Windows 10H2. Device Manager showed code 43 error on AMD Radeon(TM) Graphics device. AMD Software didn't start as well.

After updating to beta BIOS 4.26, setting CSM to custom and oprom to UEFI I was able to fix the issue.