I switched windows and now Pc crashes

[EDy Romocea]

So my computer was running perfectly with Win 7,then I decided to try the new thing and switch to Windows 10.After going through the installation and updating the drivers my computer crashd for an unexpected reason and restared itself.Didn;t pu that much taught into it that day as it was running fine,but the next day it kept crashing on anything,video games, browsing the net, even looking at the Desktop.
So i decided to go back to Windows 7 but the same problem happens, computer is still crashing(it's the same Win 7 I had earlier).
Same thing happens with Windows 8 too.
Any solutions?

 

[popatim]

did you install drivers or run any tests?

 

[EDy Romocea]

I did everything,got the good drivers, even ran Memtest and Prime and everything went fine.
And i found something strange, if I'm on a Skype call the pc isn't crashing at all.(tested)