VRED crashed during rendering - "unable to communicate with display driver"

[Matthias.wg]

Hi there,

I get an error message at the end my render process in VRED. The error message says: NVIDIA OpenGL Driver - Unable to communicate with the display driver. 

I never had this problem before. I tried render the VRED file on another PC but also here i get this error message. So it's really the VRED file itself I guess. 

Thank you for any help!

Cheers
Matthias

[michael_nikelsky]

I have never seen that message so far. A couple of questions:

Which VRED version is this?

Which GPU is this?

Which driver version is it?

How much GPU memory is used?

Any steps to reproduce this issue?

[Matthias.wg]

Yes me neither. The strange thing is that I open the VRED file on a second PC and get the same error message. 

Which VRED version is this? - VREDPro 2022.1

Which GPU is this? -   2x  NVIDIA Quadro RTX 6000

Prozessor: Intel(R) Xeon(R) Gold 6234 CPU @ 3.30GHz 3.29 GHz (2 Processors)

RAM: 192 GB (191 GB usable)

Which driver version is it? - 30.0.14.7381

How much GPU memory is used? GPU 1: 7% / GPU 2: 0% (now in the OpenGL mode in VRED)

Any steps to reproduce this issue? - no only in the final rendering mode.
Windows: Windows 10 Enterprise

thank you for your help. I hope we find a solution... 

[michael_nikelsky]

Does it only happen with that one scene? If so: Are you using renderpasses? Or are there displaced objects or substance materials in the scene? We had some issues with those in the older versions.

[mnosbues · Accepted solution]

In my experience this happens when the render process requires more GPU memory than the GPU has built in - when it happens at the end of the render you may have had the denoiser activated.

The RTX6000 has only 24GB ... the GPU memory is required for the scene (e.g. 15GB), for framebuffer 1 for rendering (e.g.  5GB for a larger render) and when you use the denoiser you need another 5GB for framebuffer 2 (which kills the card). You can use GPU-Z for tracking GPU memory usage during rendering

Btw. driver version 473.81 is quite old ... but a newer driver (or newer VRED version) will not help (only an RTX8000)

I would try to de-activate the denoiser, reduce the render size or the tips Michael mentioned ... everything that reduces GPU memory usage 

[Matthias.wg]

Thank you both for your help! 🙂