Sudden stuttering in games appeared overnight

[Strontium]

All my games started to stutter overnight with no changes to anything, hardware or software wise.

Already tried ddu, uninstalling the chipset driver (which helped previously with a similar issue).

 

Specs

Ryzen 7 1800x

Gtx 1080ti ftw3

16 gb ddr4 3200mhz cl16 g skill flare x

crucial p1 1tb

bequiet 750w straight power 11 gold.

 

I monitor everything closely via afterburner osd and no changes appeared from yesterday in temps, or else besides that after initial boot today afternoon, first time using the pc after yesterday, the stuttering appeared when moving my character in game, and was likely caused by huge drops in gpu usage

 

After reinstalling the driver w/out ddu some gpu statistics disappeared, usage frequently dropped to 0%

 

After uninstalling the chipset driver nothing changed

 

After uninstalling the gpu driver with ddu and reinstalling it normally afterburner reads everything correctly but the gpu usage still drops when I move the character in game, causing fps drops and stutter.

 

Now for the real mystery: The benchmark scores are nearly the same as normal i. e. 110 avg fps in world war z benchmark, stable fps in heaven and all that. Any stutter that occurs, occurs in game, when moving the character or in the menu by moving the mouse. This issue is familiar to me, back then it sufficed to remove the chipset driver but I've already tried that this time.

 

What could've broken overnight like this? 

 

How do I fix this?