In some games I've been playing e.g. gta v and Minecraft my gtx 1080 (eGPU) is at less than 50% load and my fps is less than 30. My cpu utilisation never goes over 50% when I play games, (usually) only 6gb of my installed 12 gb of RAM is used and I'm using an ssd so my disk usage should not be a problem. I've noticed that resource manager says my 'commit charge' is quite high. And I had (+200 MHz core clock, 5% overvolt) 40 fps in witcher 3 ultra 4k when I started the game (in velen) and I get 15-30 now (in novigrad) . I had this problem with my old gtx 970 aswell.