Computer shutting down unexpectedly

[Anthroxx]

Hello, 
I bought my pc a month back the first PSU i got was a cooler master 550 mwe which turned out to be a faulty one so i replaced it with a new one called GameMax 650 80+ bronze. After that it was running okay until it starts shutting down unexpectedly. I even checked my home wiring, checked my CPU temperature it's well below 45 degree and under 60 when i'm playing game. Any help will be appreciated.

Specs:- 
AMD Ryzen 5 3500

ASRock B450 Steel Legend
ADTA Spectrix D41 (8*2) 16gb

Zotac 1050ti 4gb

Intel 660p 512gb
WD Blue 1tb

GameMax 650w 80+ bronze

[RageTester]

All I can think off is a bad connection somewhere, might replace power cables...

Does it shut down at random times or only when playing games?

If it's option nr.2. check RAM and GPU.

[Anthroxx]

It's random mostly when idle it happens and then after two or three days runs smoothly and happen again. 

[GOTSpectrum]

Does it just shut down, BSOD or exhibit any other notable behaviour that could help us better analyse the issue?

 

when powering it back on can you simply press the power button or do you need to switch the PSU on and off?

 

 

[Anthroxx]

No it does not go to BSOD or any other thing it just shut down. And yes i have to turn off my UPS or the PSU and turn it back on and then press the power button otherwise it won't start.