Multi-GPU Path tracing rendering only uses one GPU

Development Rendering
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1

Hi,

I have two identical NVidia GPUs (Titan RTX) connected with NVLink, with SLI enabled in the driver.

Multi-GPU is enabled in the Path Tracer Preferences.

When rendering with Path Tracer, only one GPU is used (99%), but the other is idling (1%).

Is there any other configuration parameter I need to pay attention to?

Twinmotion version 2023.1.2

Windows 11 Pro - 22H2 / DirectX 12

2x Nvidia Titan RTX with NVLink/SLI Enabled

NVidia Studio Driver version 535.98 Release date: 05/30/2023

Any help will be appreciated

DxDiag.txt (150.4 KB)

2

Hello ,

Please report a bug so we can best investigate and use the 'contact us' button from the home page or follow this link:

https://twinmotionhelp.epicgames.com/s/case-community-page

For reference here are some known requirements and discussions that might help.

  • https://www.twinmotion.com/en-US/docs/2023.1/getting-twinmotion/hardware-and-software-specifications-for-twinmotion/hardware-and-software-specifications-for-twinmotion-2023-1/path-tracer-requirements
  • https://twinmotionhelp.epicgames.com/s/question/0D54z00008xoZvuCAE/multi-gpu-question

Kind regards,

Vincent B.

3

Thanks for the reply.

I created the bug report

4

Hi - I am finding that only one GPU is being used also:

Twinmotion version 2023.1.2

Windows 11 Pro - 22H2 / DirectX 12

2x 3090 RTX with NVLink/SLI Enabled

NVidia Studio Driver version 535.98 Release date: 05/30/2023

5

Hello ,

Thank you for reaching out and we are currently investigating other cases but recommend you submit a form here:

https://twinmotionhelp.epicgames.com/s/case-community-page

Kind regards,

Vincent B.

6

I am curious if this is a problem for all users or just outlier cases? I am planning to purchase another 3090 to do the SLI thing. I am hoping for a significant performance boost in rendering PathTraced animations. Is it pointless to purchase the second card for this purpose? If so, I’d rather wait for a new 5090 .