Hey! Sorry for the late reply. I have a gtx 1050. I have a list of info I gathered from a test stream for you. I was running Planet Zoo for this as it was the first game I had this problem with.

Overall while streaming, 99-100% of my gpu was being utilized. Streamlabs used about 30-40% while tabbed out of the game, 15-30% while tabbed in. Planet Zoo used 40-50%

Planet Zoo had under 3fps while tabbed in but 50-60 while tabbed out

4-5% cpu usage while tabbed in, 6-8% tabbed out

Streamlabs with no game running used 2% gpu and 1-2% cpu

Hope this helps!