GPU rendering on an RX 6800 XT never shows the desktop, and Automatic keeps choosing GPU

What happened?

With GPU rendering on an AMD RX 6800 XT, the Omarchy window never shows the desktop. It stays black, or keeps the first SeaBIOS frame (Booting from ROM...), for as long as I waited (4+ minutes). Omarchy itself is running fine behind it: Hyprland is up, typing reaches a terminal, the clipboard bridge works, and apps run. Only the Windows window never updates.

The launcher seems to notice. With GPU rendering it logs

startup: showing Omarchy (the desktop session started a while ago)

while a CPU-rendering boot on the same PC logs startup: showing Omarchy (the desktop is on screen).

Automatic doesn't recover from it. After the black GPU boot, render-probe.json records it as a good GPU boot ("result": "gpu", written during the black boot), and Automatic picks GPU again on the next start with the same result. The only way out is choosing CPU rendering in Settings. That is how this install had been left since 2026-10-08, after the same black window on v0.10.1, so it isn't new in v0.12.0.

This is not #276: inside the guest, mpv --vo=gpu-next --gpu-api=vulkan picks Virtio-GPU Venus (AMD Radeon RX 6800 XT) v1.4.315 and plays without freezing, imv opens and closes normally, and coredumpctl finds nothing.

How can we reproduce it?

1. Settings > choose GPU rendering (or Automatic), save, start Omarchy.
2. The window stays black or on the SeaBIOS frame. Typing blind into a terminal shows the guest is alive.
3. Shut down from inside the guest (systemctl poweroff; guest-exit.json records a clean poweroff), choose Automatic, start again: it boots GPU again with the same window.
4. Choose CPU rendering: the desktop shows normally.

Try Omarchy version

v0.12.0 (also seen with v0.10.1 on 2026-10-08)

Windows and PC

• Windows 11 Home, build 26200, Korean UI
• AMD Ryzen 5 5600X
• AMD Radeon RX 6800 XT, driver 32.0.21045.1000 (no iGPU; the other adapter is Microsoft Basic Render Driver)
• One 3840x2160 display at 59 Hz, 150% scaling

Diagnostics or screenshots

From vm\shell.log (v0.12.0, GPU then Automatic):

22:17:25 rendering: GPU rendering chosen in settings
22:17:25 rendering: Venus Vulkan on - display driver is not NVIDIA
22:18:10 booting - GPU accelerated (virgl + Venus Vulkan) (attempt 1)
22:18:23 guest userspace announced ready
22:18:23 GPU runtime renderer report: unreported by runtime; adapter order and environment are not proof of selection
22:18:36 startup: showing Omarchy (the desktop session started a while ago)
22:25:09 rendering: Venus Vulkan on - display driver is not NVIDIA
22:25:09 booting - GPU accelerated (virgl + Venus Vulkan) (attempt 1)
22:25:21 guest userspace announced ready
22:25:32 startup: showing Omarchy (the desktop session started a while ago)

QEMU was started with -device virtio-vga-gl,blob=on,hostmem=4294967296,venus=on -display sdl,gl=on, and the guest kernel got video=2496x945 tryomarchy.render=gpu. qemu-stderr.log only has warning: Ignoring request for interrupt vector 0.

Inside the guest:

• aquamarine: Renderer: virgl (AMD Radeon RX 6800 XT), OpenGL ES 3.2 Mesa 26.2.3-arch1.1
• hyprctl monitors: Virtual-1 3746x1420@58.96000, dpms on (a different size from the kernel's video=2496x945)
• kernel: [drm] features: +virgl +edid +resource_blob +host_visible, +context_init

A PrintWindow capture of the QEMU window is also fully black. I have a diagnostics zip and screenshots, but I haven't attached them because they include local details. I'm happy to send specific files or run builds that log more.

This report was put together with AI assistance (Claude) from a test run on the machine above.