Help with pc

[eM Attack]

I booted windows and got a black screen with my mouse so i restored to a previus day of my pc and whwn o booted it up and got in windows it was super laggy and slow i have a 4690k i5 and a gtx960 what can i do tou fix the lag and slowness

 

[Lutfij]

List your full system specs as:
CPU:
Motherboard:
Ram:
SSD/HDD:
GPU:
PSU:
Case:
Peripherals:

It's known that the Windows 8 platform was one of the worst OSes by Microsoft and it's successor, 8.1, was miles better than it. If you can please move to Windows 8.1 or drop down to 7. If you'd like you can also move to Windows 10 though I wouldn't suggest that with confidence. Although your system is laggy, you could backup your critical content and reinstall your OS.

In the interim period, please make sure your BIOS is up to date while you're using the latest drivers for your device's/peripherals.