PC abruptly switches off at random times

[bevolasko]

Hello!

I have a custom gaming computer which has been shutting itself down (more like an instant power off) in random times of the day. It may shut down after a few seconds after boot or after a couple of hours of activity. I opened the case to see if there was something odd inside. There was nothing out of the ordinary other than some dust that I eventually cleaned out. All the fans were moving too and I don't think there were any problems of excess heating. The output air was quite cool. I have re-plugged all the cables and hardware to see if there were any bad contacts but to no avail the problem persisted. The computer simply switches itself off and then it automatically re-boots.

Computer Specs:

Intel i7 870
ASUS P7H55
Gainward GTX 570
16 GB RAM (4MB x 4 sticks)
Cooler Master 650W PSU
1TB HDD & 100GB SSD
WIndows 7 x64 Home

The last time I did maintenance to the computer was a few months ago when I inserted thermal paste on the processor. The computer started to have problems a few days ago so I think it's very unlikely that I did something wrong.

I have also done some testing to see if the computer switches off at a high usage level. So I opened up UDK only too see nothing happening. I guess the random shuttdown seems to be rather ambiguous. There's no logical explanation to this.

Does anyone have any suggestions or advice?

Thanks for your time.

 

[zaka100]

Try using a recovery disk and go on system restore just to see if u downloaded something dodgy. Something like that happened with me and I did system restore.
Before it shut down, did it freeze or restart?

 

[bevolasko]

Try using a recovery disk and go on system restore just to see if u downloaded something dodgy. Something like that happened with me and I did system restore.
Before it shut down, did it freeze or restart?

It shuts down like if the power got cut off and since sometimes it happens after a few seconds of boot, it would be impossible for the OS or other software to be causing it. Thanks for the tips though.

 

[bevolasko]

I did some research and some clues indicate that my PSU could be the culprit. I don't have a spare one at the moment so I decided to get the tester out and check the different voltages. No problems detected. I also disassembled it to clean out the dust. The PC is so clean that it now makes a different noise.

I have also re-assembled and cleaned the power on and reset switch at the front of the case to see if it was unintentionally powering off the computer by itself.

Sadly, I may be left to one final option: replacing the motherboard. It may not be the best viable option that I can think of, so, this is why I'm asking you guys if you could kindly help with this matter.

 

[patonb]

That sounds like cpu heat issues.

Download coretemp, Core Temp and see how hot the cpu gets.

I know you said it feels cool, if your cpu heatsink isn't on right it'll heat up the cpu and not the case.

 

[bevolasko]

That sounds like cpu heat issues.

Download coretemp, Core Temp and see how hot the cpu gets.

I know you said it feels cool, if your cpu heatsink isn't on right it'll heat up the cpu and not the case.

The heatsink sits quite firmly on the processor and yesterday I just put on a drop of fresh thermal paste. The fan works too but, nevertheless, I'll do what you said. Thanks for the tip!

 

[bevolasko]

Ok, the maximum core temperature I managed to get was around 70°C with UDK and Minecraft loaded. At idle the temperature fluctuates between 50 and 55°C. It looks like the heatsink is doing it's natural job at dissipating the heat.

What's next?

 

[patonb]

What is UDK?

The Temps aren't bad but they are not good either. 70 with minimal load is high. My 950 runs 70 with all cores running 100%


You need to stress the computer fully, Can you run prime95
Free Software: Prime95 download - PrimeNet

Sudden shut offs are usually load related, too much heat or too much power. PRIME95 will load all cores and sufficiently see if it's power draw or heat.

When you reTIM, how much did you put on?

 

[bevolasko]

What is UDK?

The Temps aren't bad but they are not good either. 70 with minimal load is high. My 950 runs 70 with all cores running 100%


You need to stress the computer fully, Can you run prime95
Free Software: Prime95 download - PrimeNet

Sudden shut offs are usually load related, too much heat or too much power. PRIME95 will load all cores and sufficiently see if it's power draw or heat.

When you reTIM, how much did you put on?

UDK = Unreal Development Kit

Thanks but as I said before my PC turns off independently from CPU usage and heat. It turns off even if the PC was idle for half an hour. Luckily, today the PC was working normally and it didn't turn off itself.

 

[Reapt]

Like it was said earlier. CPU heat issues or a faulty PSU. I would find a new PSU., and put it in and see if the computer behaves normal.