FPS/Stutter dropping on full screen?

[Donk323]

So I have a GT62VR-6RE-Dominator-Pro, I bought a predator xb1 monitor and have it overclocked to 180 hz and gsync on full screen, when I play games like League for example when I play on fullscreen Its running fine, then drops to like 1-5 FPS for like 5-20 seconds then goes back to fine and repeats on and off every few 20-40 secs. But when I play on borderless/Window it runs fine with no drop like that, I tried putting Gsync on both window and fullscreen and I have the same problem on borderless just not as often but I don't know whats causing this problem. I would appreciate any input / support on this issue if anyone has any info on fixes etc. Thanks~

 

[Donk323]

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