Optix fail - "CUDA_ERROR_ILLEGAL_ADDRESS"

[Curds]

I'm trying to render Karama XPU in solaris on a scene with 2500 USD instances and I repeatedly get this error message "KarmaXPU: device Type:Optix ID:0 Name:"NVIDIA GeForce RTX 5090" has registered a critical error "Unable to create CUDA context "CUDA_ERROR_ILLEGAL_ADDRESS" (maybe old driver? requires 570+)", so will now stop functioning. Future error messages will be suppressed"

Sometimes it renders ok in the viewport but often fails and only renders on cpu, and wont reset unless I reopen the file. If I try to render though the USD render rop, the GPU sits idle and the CPU works at 100%

I've tried updating drivers and going back to old drivers (this is the only solution I could see people posting online) but it doesnt seem to help.

Removing textures doesn't seem to help and reducing instance count doesn't seem to help.

I thought it might be a VRAM issue but the VRAM is only operating at around 30% when rendering.

 

Any suggestions would be greatly appreciated, I'm at a bit of a loss as to what to try next.