Computer is running very slowly after fixing a defective power supply

[tempacc1234]

I've had this problem where my computer would randomly shutdown after a couple of minutes of gaming. After more than a week of trying to fix the problem I've concluded this was because of a defective PSU. After I fixed this problem however, a new problem arose. My desktop is now running very slowly like I can't even properly scroll down in Google Chrome. Also I won't get more than 25 fps anymore on game that I used to get 100+ fps on. This happens on both graphically intensive games and very not intensive games.
I've tried clean installing my graphics driver and reverting to an earlier driver but nothing seemed to fix it.
My GPU usage does not got above 35% even on demanding games with the settings turned up. I'm almost 100% sure that it's not using the integrated GPU because the usage does go up when I start a game. I've checked this through MSI Afterburner.
I haven't changed or replaced anything in my computer apart from the power supply. I got the same power supply as the one I had before I got this problem as it was still under warranty.
My GPU temperatures don't exceed 60C under load and my CPU temps don't exceed 52C.
I haven't overclocked anything.

My specs are:
ASRock Z97 Extreme4 motherboard
Intel i5-4690k
Asus STRIX GeForce GTX 970 DC 2OC
Corsair CX750M
HyperX Fury 16GB RAM

 

[Kiril_Petkov]

Simple check you could do it to boot in save mode and run browser there. If you PC is "slow" again, that mean the issue is prob in HW, if the PC working fine then the OS is broken or some driver not necessary the GPU. The other check you could do to run burn test to check can you load the PC to max.

 

[tempacc1234]

Simple check you could do it to boot in save mode and run browser there. If you PC is "slow" again, that mean the issue is prob in HW, if the PC working fine then the OS is broken or some driver not necessary the GPU. The other check you could do to run burn test to check can you load the PC to max.

For some reason I don't have any internet connection in Safe Mode so I can't really test that. I've ran burners for the CPU and GPU and both make the usage go up to 100%.

 

[Kiril_Petkov]

Boot from life cd then some linux. Btw what OS you are using ?
P.S. Check do you have network driver for the lan card.