Hello! I must be missing something. I can't seem to find how to connect a bump map onto an MtlXStandardSurface in Karma XPU.
Can anyone help?

As far as I know, you cannot do that currently.

Your options are:

- Use a normal map instead (careful, you need to use a mtlxnormalmap because materialx expects normal maps to be world and not tangent, this node will do it for you)

- Use real displacement

Thank you! I've managed to get it to work with mtlxnormalmap, but here is the promblem: The difference in quality between XPU and CPU is huge. It even seems to be a bug or something on the light. Any ideas?

My understanding is that the function that computes the reflectance is different for Karma and KarmaXPU. So what you are seeing is at least from what I know technically not a bug, just two different results.

For the same reason you cannot (at least currently) mix frames rendered by regular Karma and XPU. Other stuff has similar differences (for example volumes render a tiny bit different in both).