Computer Reboots. Possible Power Supply issue?

tampler

So, I was watching some stuff on Friday night when my computer suddenly switched off by itself. No warning, all my windows closed and it shutdown. Thankfully, a press of the power button, it came back on.

So, the following morning, i'm browsing the net, when suddenly the computer does the same thing again. It shuts down by itself.

I press the power button, the computer comes on, the fans run as normal and the lights on the motherboard light up as normal, then about 5 seconds later. it shuts down.....then it comes on again....and then quickly shuts down again.

So I decide to leave it alone for 10 - 15 minutes and unplug it and get a cup of tea. I come back, plug the computer back in, and it turns itself on without me even pressing the power button in front. It has never done this before. Generally, I would plug it in, press the switch at the back of the computer and then press the power button on the front and the computer would come on without a problem. However, it now constantly powers up, suddenly stops, and then powers up again.

Luckily I was able to spam the delete button, reached the bios and select the fail safe option. The computer worked fine for the rest of that day. I was able to play games like Crysis and Warcraft and do other tasks without any problems.

Today, I plugged it in, press the switch behind the computer, and it comes on itself without pressing the power button, and constantly reboots. Nothing I have done has fixed it.


SPECS!
Windows 7 64 bit ultimate.
Intel i7 920 2.66ghz (Note that it was over clocked to 4.00ghz from the place I bought it from)
Sapphire ATI radeon 5850
Antec 1200 case
Gigabyte GA-EX58-UD5 motherboard.
Corsair XMS3 6GB DDR3 Ram (3 sticks, 2GB each)
Seagate Barracuda 7200.12 1TB hard drive
Corsair TX 650W ATX SLi Compliant Power Supply .

Just a few things to mention:

1. I have not upgraded the computer since I got it back in January. Only part that was replaced was the 5850, as it was dead on arrival. The site I got the computer from (overclockers) was quick to replace it, and has been working fine ever since.

2. It reboots before Windows even has a chance to load and before the motherboard manufacture screen appears.

3. The time it takes for it to switch on again can vary. Sometimes it will switch on and then switch off 5 seconds later. Other times, it might switch off and wont switch back on for 2 minutes.

4. I toke out the graphics card to see if that helped. It did not.

5. I unplugged the hard drive to see if that helped. It did not.

6. I tried booting it with one stick of ram, and changed the slot it was in to see if that helped. It did not, and I tried it with the other 2 sticks.

7. The motherboard does not make any beeps. The LED warning light changes constantly as it usually does when the computer is turning on.

8. All the fans are working. The graphics cards fan works. The CPU cooler works, and the cases fans work.

9. Nothing was overheating. Temperature levels for the CPU and GPU were fine.

10. At present, I cannot reach the BIOS screen.

From what I have been reading, it seems the Power supply is on its final knees. However, I just want a second opinion before I decide to buy another one.

So guys. Any ideas?

corkcomp

faulty power supply or lose connection but i wouldnt rule our proc or ram, might be no harm to (carefully) reseat both

JonathanAnon

Are you sure it has nothing to with the overclocking.. maybe you pushed the processor too far... ? Or maybe there is an issue with the processor fan.... (though I have read that you say that it is NOT overheating)... there's just something about the randomness of the types of restarts that would make me look to the processor / fan.

Gruaig

How long have you had the pc? Something simlar like this happened to me a while back. I opened my pc and could see that there was alot of dust around the fan stopping it from spinning i cleared it out and it works good. It was just overheating. try keep your laptop of bed/couchs

tampler

Hey guys. Sorry for the late response and thanks for the replies so far.

Just a little update:

The computer was working fine yesterday. Even turned it off for a hour and it turned back on no problem. No random shut downs either.

During this time I downloaded coretemp so I could keep an eye on the CPUs Temperature. While the computer was idle, all 4 cores were usually somewhere between 35 - 41°C. I also downloaded Prime95. When that was running, the cores shot up to its late 50s, with core 0 usually hanging around 61°C. There was no reboots during this time.

Sadly, it appears the computer is on strike again today. Pressing the power button causes the computer to turn on but it ends up shutting down. Although this time, it can actually pass or reach the windows loading screen. Also, after it shuts down, it wont try to boot up again for another 2 - 3 minutes.

Hopefully, If it decides to start working again, and it reaches the desktop, I plan on downloading memtest to see if its a memory issue.

Are you sure it has nothing to with the overclocking.. maybe you pushed the processor too far.

Again, it was not me who over clocked it, but Overclockers.co.uk. And it was working fine up until now. Even though I reset it back to its default settings, it still refuses to boot up at this moment.

How long have you had the pc?

Since January.

I opened my pc and could see that there was alot of dust around the fan stopping it from spinning i cleared it out and it works good.

I spent most of Monday clearing out any dust I could find. All the fans seem to be running fine.

try keep your laptop of bed/couchs

Its not a Laptop


Again, thanks for the responses people. Greatly appreciated!


EDIT 15:47: The computer was able to boot up into Windows and I was able to download Memtest. Its running as I type. Will report back soon.

death1234567

I had a similar issue before and it was the PSU. I would test first with a friends PSU or something to see if thats the problem.

JonathanAnon

death1234567 wrote: »

I had a similar issue before and it was the PSU. I would test first with a friends PSU or something to see if thats the problem.

I am normally fairly reluctant to suggest this sort of thing, as there is the possibility that you could end up with two broken PCs.... slight chance, yes, but I wouldnt fancy the embarrassment of that on my hands..

digme

JonathanAnon wrote: »

I am normally fairly reluctant to suggest this sort of thing, as there is the possibility that you could end up with two broken PCs.... slight chance, yes, but I wouldnt fancy the embarrassment of that on my hands..

enjoy the reboots so

witnessmenow

Lets break it down:


Heat - You've ruled it out

PSU - Possible , find out by switching out with a friends or get one of these maybe (never used one myself)

Ram - Possible, I would have thought it would have cause blue screens rather than shutdowns though? Ubunutu installation cd has a memory tester built in.

CPU - If its surviving Prime and is passing the FFT then its hardly an OC problem.

GPU - If its surving crysis its probably not this. Re-seat it if you've tried other options.

Motherboard - Maybe, hard to diagnose though. Reset the CMOS anyways and see how it goes.

Case - Power button could be faulty maybe? Unlikely though