Hi, recently i added another cheap used RTX3080Ti to my PC just to experience the dual GPU benefit when using Topaz AI.
My system is:
AMD Ryzen 9 5900x
Gainward RTX3080Ti Phoenix
Asus RTX3080Ti TUF Gaming
64GB DDR-4 3600
Since my MSI 49” 5120x1440p OLED (essentially a dual 1440p monitor without center bezel) is support Picture by Picture mode, i connect both GPU1 to HDMI1 and GPU2 to HDMI2 and show both desktop side by side.
The GPU is detected in HWinfo64 and GPU-Z, both running at PCIe4.0 x 8. Here’s the problem,
I can see both RTX3080Ti in the Topaz Video processing settings, however when i choose let say GPU2 while the GPU1 is set as main display in Windows 11 display setting, the rendering will start at GPU1 regardless the setting. Reverse happen if i select GPU2 as main display.
I have 2 mitigations right now.
- In dual monitor setup mode, open instances 1, regardless GPU setting, select GPU1 as main display in Win 11 display setting and start the rendering on GPU1. Then start instances 2, now switch the GPU2 as main display and start the rendering in GPU2, now both GPU will render on 2 different file. OR
- In single monitor setup mode, with HDMI connected to GPU1, open instances 1 and start the rendering on GPU1, regardless GPU setting in Topaz. Then start instances 2, now unplug the cable from GPU1 and connect to GPU2 and start the rendering in GPU2, now both GPU will render on 2 different file. I won’t do this since my monitor can support PBP.
This is not only happen on Topaz Video, but to Furmark2 and any other rendering tools as well. I can’t get a definitive answer from google and AI tools as well. What’s happening here? It looks like the rendering path only default to the GPU that plug with monitor or set as main monitor if it was set as dual monitor. I even bought a dummy HMDI plug to trick the system, but the outcome is same. This dual GPU solution definitely doesn’t sounds promising and intuitive at all.
Just to check is this an expected limitation on the dual GPU system?
