AMD 780M Vulkan renderer leads to corrupted textures

[Not4ce]

Current Behavior

Enabling vulkan on rdna 3 based cards, such as 780m igpus break pebbles and textures in-game. Also broken shadows that eventually garble and have corrupted textures. Observed in MK8 and BOTW. No graphical or texture enhancements applied, can be replicated on two seperate 780m devices

Vram allocation does not change anything. Only fixed by changing renderer to OpenGL, and seems to be Rdna3/780m specific. Was unable to test on a discrete rdna3 card, no issue on Rdna2 and Nvidia counterparts (6800xt and 3070)

Expected Behavior

Nil graphical issues and not garbled textures

Steps to Reproduce

Enabling vulkan renderer
Playing any game: Breath of the wild etc

System Info (Optional)

OS: Windows 11 22631.3374 KB5035942
GPU: 780M on Ryzen Z1 Extreme and 7840u

Emulation Settings (Optional)

Default with no mods or changed

Also Tested with:
BCML enabled
Second Wind enabled
No graphical mods or changes on 1.2.6 and 2.0 cemu

Logs (Optional)

log.txt

Tested with OpenGl that had no issues, followed by switching to Vulkan with issues (UMA frame buffer set to 6gigs on system)

[Exzap]

AMD has a track record of needing 1-2 years to get their drivers up to standard (we have reports like this for every new generation). This combined with the fact that it works on everything else points towards an issue with their driver. However, we don't know for certain unless someone does some digging. I will keep this open for visibility and in case someone with the affected hardware and the necessary know-how wants to look into this.

[Exzap]

Something you can do to help in the meantime is upload a Vulkan validation log. The steps to do this are:

1. Download the Vulkan SDK and install it from here (you can uninstall it afterwards)
2. Restart your PC
3. Open Cemu (use a recent version like v2.0-78), in the menu tick Debug -> Logging -> Vulkan validation layer
4. Trigger the glitch (avoid doing too much other stuff, it makes the log harder to read)
5. Upload log.txt

[Not4ce]

AMD has a track record of needing 1-2 years to get their drivers up to standard (we have reports like this for every new generation). This combined with the fact that it works on everything else points towards an issue with their driver. However, we don't know for certain unless someone does some digging. I will keep this open for visibility and in case someone with the affected hardware and the necessary know-how wants to look into this.

Thank you for getting back. I had a similar line of thought and I found this very strange, as I am unable to replicate this on RDNA 2

As per AMDs own documentation, their vulkan implementation is the exact same on both RDNA 2 and 3. I wish I had a discrete RDNA 3 card to test this, but if a future driver update from AMD remedies the issue, I will update or close this ticket

As it stands, I am disappointed at amd, as all handheld devices use AMD Apus, and I am unable to distinguish if this is an APU driver or RDNA 3 issue

PS: I tried seperate driver versions and ddu with no success. Thank you for keeping an eye on this

[Not4ce]

Something you can do to help in the meantime is upload a Vulkan validation log. The steps to do this are:

1. Download the Vulkan SDK and install it from [here](https://sdk.lunarg.com/sdk/download/latest/windows/vulkan-sdk.exe) (you can uninstall it afterwards)

2. Restart your PC

3. Open Cemu (use a recent version like v2.0-78), in the menu tick `Debug -> Logging -> Vulkan validation layer`

4. Trigger the glitch (avoid doing too much other stuff, it makes the log harder to read)

5. Upload log.txt

The last version I tried which is this was broken

However, 2.0-78 has seemingly fixed the issue! Heres the log attached below with vulkan debugger

What I can conclude is the last version I had downloaded (2.0-46) just did not play nice. Strangely my 6800xt never had issues with any version (including 1.2.6), so its rdna3 driver related bug on older builds
log.txt

Image of 1.2.6 corruption:

Thank you for walking me through this

[Not4ce]

Welp, @Exzap turns out Cemu2.0-78 only fixes the pebbles or greatly reduces the amount of initial corruption. After further playing the game and wind waker, the issue is still present. I have recorded a video for reference and the prior vulkan debug log is still valid

As usual, I'm unable to replicate this on my desktops with rdna2 and ampere cards and can reliably repeat this on any 780m based device like Ally/Win. The only fix is using OpenGL and rolling back drivers doesn't change anything

Kindly let me know if you require further logs or information, kind regards

vulkan.bug_1.mp4