COmputer unexpected Shutdown

[oroalej]

hello, recently my computer started to shutdown on his own and open afterward. when it shutdown, even the power supply fan stops.i try to reinstall windows 8 but the problem is still there.i try to run eset smart security 8 and malwarebyte but they found nothing..My setup is only 3 months old. please help me.thank you..

my Spec,

MSI GTX 750ti
i3-4160
GA-H81M-DS2
corsair vs 450
hyperx 4gb x 2
CM hyper 212x

 

[Vic 40]

If you take the750 ti out will it still do that?Not to suspect the gpu,but more the psu.Can you test the psu with another pc,maybe from a friend or ...

 

[oroalej]

If you take the750 ti out will it still do that?Not to suspect the gpu,but more the psu.Can you test the psu with another pc,maybe from a friend or ...

I already tried removing gpu, still turning off. tried removing one ram, still turning off. tried removing other ram, still turning off..
Can it be the motherboard's fault? I currently testing PSU, it is almost 2 hours and still not turning off..

 

[Vic 40]

Can be the motherboard.
How are you testing that psu?
Temperatures are fine too?

 

[oroalej]

Can be the motherboard.
How are you testing that psu?
Temperatures are fine too?

The PSU is causing the issue! thank you very much, can you recommend PSU model or brand to buy?

 

[Vic 40]

For a broad choice can you look at this,
http://www.tomshardware.co.uk/answers/id-1804779/power-supply-unit-tier-list.html
look if you can for units from tier 1 or 2A/B,there's an updated new list but don't have the link yet.This should do anyway.

If you want specific units give the site you're looking at,preferably the psu list,or if the pcpartpicker can be used let me know.