gpu at 98% low settings

[Red_TC]

I have Asus rog strip 1080, i7 8700k. and 16 gigs of ddr4 ram

less then a week ago I was able to run overwatch low medium settings at 240fps with my 240hz monitor 

I just swapped cases and now my GPU is on my top PCIe slot [I know it was always supposed to be there I just never had it] and now my fps has gone all the way down to 100 fps 

and my GPU load is 98% 

I have all my drivers installed in only 1080p

I'm not streaming or anything else to bottleneck my GPU or extra stress 

I've run a security scan to check for virus and all that

I don't know why it's happening and would appreciate any responses