Low gpu usage

[s26rech]

I have a 980ti sli configuration and it always worked fine. 1/2 months ago almost any game started heavy stuttering due to low gpus usage, in fact the cards always run low usage but never 99% ( 60/70/80/50 etc ), this is very annoying and it also happens in easy games ( rocket league doesn't go above 200 fps and it keeps stuttering ) and even using a single gpu in any of the pcie slots. I already tried to check temps, install differents drivers, overclocking cpu and ram, kboost, pcie power management, formatting to a fresh os, memtest and checking cpu and ram usage. I think it could be due to a bios/os setting because I already tried everything hardware and driver side but it could be wrong of course.
Any help?

i7 6700k ( stock due to high temps but even clocking it to 4.6ghz makes no effect )
Z170 Pro Gaming
Corsair H100i
Evga P1000
WD Black
Samsung 850 Pro Evo
2x4gb Kingston Savage 2133mhz
Sli 980ti g1 gaming
Haf X
W10 ( last build )

 

[ZeusGamer]

This might be a dumb question but let me ask you anyway, when you play your games, are you making sure that they are on Fullscreen in the game settings? SLI does not work on windowed mode or borderless windowed mode. Also, try downloading Nvidia Inspector and set the power management to prefer maximum power in the game.

 

[s26rech]

This might be a dumb question but let me ask you anyway, when you play your games, are you making sure that they are on Fullscreen in the game settings? SLI does not work on windowed mode or borderless windowed mode. Also, try downloading Nvidia Inspector and set the power management to prefer maximum power in the game.

Yes, of course I play in fullscreen, I even tried several times to switch between windowed and fullscreen mode to make sure that wasn't a bug. I'll try nvidia inspector, but changing the power management in the nvidia control panel didn't help!

 

[s26rech]

Should I select "PREFERRED_PSTATE_PREFER_CONSISTENT_PERFORMANCE"?

http://imgur.com/a/0AodT