GPU at 100% only on lobby screen

I a noticing my gpu usage is at/very close to 100% when in the lobby screen, and in game like 5-60%. Is this intended? My FPS on lobby screen is like 126, pretty high (144hz monitor), and in game like 40-70 fps.

I found the fix: limit fps with 5 fps, I used bandicam. drops to 2% usage. Unfortunately, this doesn't work if you have the game in the background. Weird huh?