Pc's Random shutdowns

[3heroofasgard]

Recently I've had a huge voltage drop in my apartment which caused the death of my Pc's power supply. So I found an old one which has 200 Watts less power and replaced it. And everything was fine for quite some time. But then something went wrong and my Pc started to overheat and eventually shut him self down.
Does this mean that my current power supply is not powerful enough to support my graphic card or my CPU?The software that I've been using to check my graphic card temperature has shown increasing up to 80+ degrees when using multiple apps at once.
And is there a way to reduce the pressure on power supply or just remove the auto shutdown function from my CPU? Or is it necessary to buy a new power supply?
Thank you very much for your time!
p. s. My OS set up and other software staff(drivers and things) are perfectly fine and are updated to the latest version.

 

[sizzling]

Please list full pc spec including make and model of PSU and how old it is.

 

[T_T]

First of all, yes, your PSU is likely to blame. Second, you can't and don't want to disable the auto shutoff of the CPU - it's for protection from damaging the CPU and motherboard. Get yourself a good quality PSU from well known brands, such as Corsair, Antec, etc. Don't be cheap, either. Get one that supports your load, which can be determined here.