Hi,
Getting wierd results with RTX4090 and Karma XPU. Nvidia Studio Drivers 551.23 (latest). Houdini 20.0.590, clean install.

5995wx + 4090 gives these (circled) artifacts:


5995wx alone (using KARMA_XPU_DISABLE_OPTIX_DEVICE in houdini.env to disable GPU) gives no artifacts:


Test system using 2080Ti and 10900k also gives no artifacts (using same nvidia drivers and Houdini version, clean install):


What could be causing this and how can it be fixed?

Sorry slow reply.
So to be clear...

Rendering with only the EmbreeCPU device works fine?
ie, KARMA_XPU_DISABLE_OPTIX_DEVICE=1

And when testing the GPU device in isolation (ie KARMA_XPU_DISABLE_EMBREE_DEVICE=1)
then...

• RTX4090 produces artifacts?
  
• 2080Ti has no artifacts?
  

Is that correct?
If so, let's try debugging some of the texture features and continue testing on the RTX4090...
try some of these envvars and let me know how you get on.
KARMA_XPU_OPTIX_SPARSE_TEXTURES=0 (default is 1)
KARMA_XPU_OPTIX_HQ_LINEAR_FILTERING=1 (default is 0)
KARMA_XPU_DISABLE_MIPMAPS=1 (default is 0)

thanks

Hi


I have the same issues with my 2080, I thought that a new Gpu (4090) will fix the problem but as I read your post it will not..

I tested to add this envvars.
KARMA_XPU_OPTIX_SPARSE_TEXTURES = 0
It fixed the issues but Optix doesn't start (initializing) so very poor performance

I tried also with this 3 envvars. Same result
KARMA_XPU_OPTIX_SPARSE_TEXTURES=0 (default is 1)
KARMA_XPU_OPTIX_HQ_LINEAR_FILTERING=1 (default is 0)
KARMA_XPU_DISABLE_MIPMAPS=1 (default is 0)


Is there any other solutions to fix it?

Thanks

I had the same error, but I was able to solve it by downloading and installing the latest production build, where the error no longer occurs.

Dobri12
I had the same error, but I was able to solve it by downloading and installing the latest production build, where the error no longer occurs.

Interesting.
We did fix a texture-tile bug in 20.0.666
It would be interesting to know if it solves this issue too

Tukifri
I have the same issues with my 2080, I thought that a new Gpu (4090) will fix the problem but as I read your post it will not..

What version of Houdini are you on?