Is my motherboard or CPU dead?

ledburyr

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Oct 7, 2010
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I assembled a new PC for myself not that long ago (roughly 6 months) and all was running fine until last night. As I was sitting at my PC I had a look a something on my phone for a few minutes tops, when I looked back up to use my PC it had frozen. I hit the reset button and didn't think too much of it; I carried on just using the internet and went into my living room to watch a bit of TV. When I came back, my PC was frozen again. I came to the conclusion that it must have been something I installed recently, which lead me to believe Games for Windows Live was the issue, as that's the only thing I'd recently installed (apart from Dead Rising 2, but I assumed GFWL had some service running in the background hanging my PC).

One thing to note above, I was not doing anything intensive on my computer at all. So I don't believe the issues I describe later on to be temperature related.

Anyway, I booted it up again a while later and started playing Dead Rising 2. All was fine for an hour or so perhaps, and yet again the screen froze. It probably stuck for about 5 seconds before hearing a click and my computer turning itself off completely. Initially, I couldn't turn it back on, however after a couple of minutes it began working again. As it booted I decided I'd go in BIOS and see if I could see any temperature readings that could be part of the issue (even though the components would have had a few minutes to cool by then). Before I got the chance to figure out where the menu option for this was in my BIOS, yet again my PC turned itself off with a click sound. Since then, I haven't been able to turn it on at all. Pressing the power button does nothing: no fans, no POST or whatever; absolutely zilch.

I initially assumed by PSU had just died for whatever reason, however if I remove the 24 pin motherboard connector and do the paperclip test, my PSU's fan starts (although it does look a little slow; I'm not certain how fast it's meant to spin), and the fans on my case start up, as well as the LED's.

I've since tried all sorts: different power cables, different wall sockets etc. and I'm quite convinced it's not the PSU. I've tried reseating my RAM, trying each stick individually, even trying it with no sticks so I'm guessing it's not RAM either. I've unplugged my SSD and blu-ray drive - still nothing. I don't have a spare graphics card to test out, but I've tried running it without one for the hell of it and still nothing. I wouldn't have thought any of these things would prevent a power on anyway; the least I would expect it would turn on but not do anything, but I gave them a shot at least.

I guess really this leaves me with two options: it's either my motherboard or CPU. I've had a fairly detailed look at my motherboard and I can't see any obvious problems such as it being shorted to the underside of the case or anything. My CPU was overclocked from 2.6 (?) GHz to 4.2, but I had very good cooling for it and it rarely ever went anywhere near 40 degrees, even under load, so I don't think I've overheated it and knackered it (even then, surely the safety would kick in and turn it off before it fried?).

So really I'm inclined to think it's my motherboard, however when the PSU's connected the manufacturer's logo still lights up, and so do the overclocking buttons on, so it's obviously taking in power (removing the 24 pin connector causes the lights to turn off after a few seconds).

I'm thoroughly confused, and the only way I think I can sort this without any help is to shed out money on the components I think might be dead!

Could anyone voice their thoughts on what the problem part is, or perhaps suggest further tests for me to conduct to pinpoint the exact problem?

I appreciate your help :) :)
 

ledburyr

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Oct 7, 2010
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Well, all I know is that that plugged in, the lights on my motherboard light up and that if I stick a paperclip in the green and black wires on the 24 pin connector, my PSU fan turns on and so do the fans and LED's on my case. From what I've read online, this signifies it's not a problem with the PSU, but I'm not 100% on it though.

I unfortunately don't have a multimeter to test it properly, or a spare 1000w watt one I can borrow to put in its place to see if it works :(.

I guess it isn't necessarily the 24 pin one that's the problem though? If the other 8 pin one that goes into my motherboard (is that the CPU power?) one is knackered I guess it wouldn't boot, would it? The one I have plugged in there is labelled 'P3', so I'm a bit reluctant to plug in any other 8 pin ones as they're all marked specifically for PCI-E.

I'd love it to be the PSU though, that's the cheapest part to get if I can't get a replacement!
 

Gekko Shadow

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Oct 4, 2010
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Lol the 8 pin is definitely for power goes to the motherboard, without it most definitely won't start.

Hmmm. What kind of thermal paste did you use? And when you OC'd this did you run a stress test to test stability? (like prime95?)

Most motherboards would have "the safet...kick in and turn it off before it fried" - but this one would freeze. Maybe it was a sign? lol.
 
The paper clip test only shows that the AC/DC conversion works; it does not show that the hardware is getting the correct amount of power. A multimeter is the only way to know for sure what the PSU is putting out.

While we're on the subject, a dying PSU certainly can cause the exhibiting symptoms you've described. Without sufficient power, your RAM and CPU are greatly affected.

The system will 'freeze' or hang because the RAM isn't working (properly). Similarly, without enough power to your CPU, it will shut down because its not getting enough power. In fact, think of a flashlight with nearly dead batteries... The flash light may illuminate, albeit very dim, and then turn off (well the bulb, anyway) because of insufficient power.

You should work through the troubleshooting guide (link in my signature), as it is designed to help you solve the no boot/no display issues.
 

ledburyr

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Oct 7, 2010
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Thanks all :)

I think the next step is to get a multimeter, I expect my dad has one so I'll drop by his place tomorrow. Out of anything, I'm hoping it's my PSU that's dead so it'd be great if it is.

The link in your signature was a handy guide T_T, it gave me a few extra things to test that I hadn't thought of. Still no conclusive results, but I'll see what the results of the multimeter test are and take it from there I think!