Bad FPS, Good Computer

[PekkaLegend]

(I'm typing this for a friend currently) Here are the specs:
i5 4690k 3.5ghz
MSI Nvidia GTX 980
ASRock Z97 Extreme4 MB
EVGA 650W
2x8GB Corsair RAM
1tb WD HDD
250gb Samsung 850 EVO

I'm getting only around 30-60 FPS on CS:GO w/ low graphics, while I should be getting 10x that. So far i've downloaded my motherboard and GPU drivers. I've also tried to use an older driver for my GPU, but that doesn't seem to work. Also, this isn't just in CS:GO, I only got an average 30FPS for a Unigine Valley benchmark. I've tried putting my graphics on low, and went to the Nvidia Control Panel and set my graphics to performance, no difference. I'm getting an average 40 celsius for my CPU on idle and same goes for my GPU. Please help.

EDIT: I have windows 7 professional 64-bit by the way.

 

[Outlander_04]

What version of windows?

 

[PekkaLegend]

windows 7 professional 64-bit

 

[deer_hunter]

maybe the power supply it's not working properly ,also open you case and make sure all cables are correctly plug in on motherboard ,gpu,etc, what's the gpu temperature ? try install windows 10 .

 

[PekkaLegend]

why do you think its my psu? what are symptoms?

 

[Outlander_04]

I would clean out all the graphics drivers and then reinstall the latest version

 

[PekkaLegend]

do you know a program or how to clean the drivers?