Games lagging gpu usage spiking up and down

Gigabyte1321

Commendable
Jan 14, 2017
6
0
1,510
Recently, aproximately all my game started lagging and severe frame dropping, and they were perfectly fine 1 week ago with 50 60 fps on max and now they are 40 dropping to 15 20 fps. I did fresh install of windows searched for malware reinstalled drivers but nothing seems to work.
Specs: i7 7700k
Msi r9 390x oc edition
Gigabyte z270x-ultra gaming
1 tb hitachi hdd
250 gb 850 evo
850w corsair rmi
Fractal define r5 case
The screenshot is from approximately 20 mins of gta v
Plcvg

The video card and the psu is from december 2015 so its not that old. I dust off my pc once a month.
Its still in warranty so i can use that as a last resort