Question / Help Multiple GPU, Multiple Monitors

[Lord Anubis]

I was wondering if i could get some expert advice or practiced opinion.

I stream a bit of VR which is both CPU and GPU intensive depending on the title. I have an i7 7600k, 1080ti and 1080. Both monitors and the Vive are connected to the 1080ti. Some days it works ok and other days it suffers frame drops to the point where i can't stream at all and my OBS is slow to load and transition scene on occasion.

I am using animated overlays as a browser source, i have them to disable when not active so not to chew CPU. I also use the Nvidia encoding.

Would i be better off plugging my 2nd monitor that displays OBS into the 1080 that's doing nothing While leaving my Vive and main monitor plugged into 1080ti. Would this help performance at all. Would that distribute the GPU load across both cards? or does that gain nothing.?

Thanks in advance

 

[koala]

Physically remove the 1080 from the PC and do all stuff on the 1080 Ti. This way, you get the complete pci-e bandwidth of 16x for the ti. As long as 2 cards are installed, each of them only get 8x, regardless if you use both of them or only one.

Running your app on one card and OBS on the other card isn't recommended as well, because the raw video data has to be transmitted from one card to the OBS card via pci-e bus, which has only 8x for each, and then the data is transmitted another time from the OBS card to CPU memory.
If you use nvenc, then it is transmitted over the pci-e bus another 2 times (uploaded raw data, encoded in GPU, downloaded encoded data). Added to previous pci-e transmits, this results in huge stress on the pci-e bus, which may overload it. If you use only one card and physically remove the other one, you lower the pci-e bus stress tremendously.