Multi GPU Unexpected Performance Hits

[Tyrael]

Hello, I've recently invested in a streaming rig to do some high quality streaming with a virtual avatar but I've run into a couple issues that I'm not sure how to fix. I tried this whole setup on my old PC with single 2080 super, but it didn't have nearly enough horsepower to do what I needed.

 

When I stream I have motion capture software open (MoCapForAll) which uses machine learning and webcams to do body tracking. I pipe the mocap data into Unreal Engine where I have a fun virtual set with a character to receive said mocap data. On top of this I want to be able to play games while streaming, which  is why I need 2 GPUS.

 

Using Windows 11 I have it set up so the motion capture and Unreal Engine set are running on one graphics card (3080) and my game is running on another (3060 Ti). I have the 3080 plugged into one monitor and the 3060Ti into the other. (3060 Ti is in the first slot on the Mobo). Each card is plugged into separate monitors and I make sure each program is on the monitor corresponding to its GPU. Now here comes the problem...

 

Despite all of this, the motion capture program and Unreal Engine takes a sizeable performance hit when I am playing a GPU intensive game such as Halo Infinite. If I click out of the game and use anything that isnt GPU intensive, such as chrome, everything is fine. Halo is still running at high fps in the background. Everything seems to work fine with a less intensive game such as Morrowind. So it looks to be an issue where these programs are somehow coupled with the other GPU, or they are given too low of priority to run well. I've thought about possibly passing through the 3080 with mocap and unreal engine into a virtual machine so that they could potentially ignore the other GPU being used, but this seems like a lot of work when there could potentially be an easier solution.

 

Any ideas?

 

Thanks for any help in advance!

 

For other pc specs I have:

Asus Strix X570-E Gaming MOBO

Ryzen 9 5900X

Unreal and Halo are on a Seagate Barracuda 3TB HDD

Mocap is on a 1 TB Samsung 970 EVO SSD