5 replies to this topic

[greedo]

I have a media center PC that has been shutting down unexpectedly. I have run out of ideas troubleshooting it. Any help would be greatly appreciated.

When it shuts down it just dies – no blue screen, no error, just total loss of power. It will not turn back on until I have unplugged the power cable for several minutes. Then it will boot up fine and work normally. The clock stops while the PC is shut down (e.g. if I leave it off for 1 hour the clock becomes 1 hour slow). Also, the BIOS seems to be getting wiped back to defaults.

I am pretty confident I've ruled out the most obvious issues:
1) I replaced the PSU with an identical one (it's a proprietary case) as the PSU is more than adequate for the components (see below)
2) Replaced the BIOS battery (because of the time issue)
3) Not overheating – the PC doesn't feel remotely warm after shutting off – I can touch the CPU heatsink and it is barely above room temperature. There also seems to be no correlation between what the PC is doing and when it shuts off. It will still die when the CPU is not being actively used, and the PC never does anything more strenuous than playing video.
4) Software is ruled out as the PC only runs Windows and XBMC (plus a few codecs and winrar). I got the same problem after a fresh Windows install before installing any 3rd party software.
5) Cleaned and re-applied thermal paste to the CPU
6) Ran a RAM test from a special boot disk - no errors on the first pass, but the PC shut down at around 20 mins in, which is the usual time it crashes, which rules out software as Windows wasn't even booted.

Any ideas?

The PC is a Core i3 (no separate GPU), used only as a media center. There is no extra hardware except the HDD and USB dongle for wireless keyboard/mouse. The HDD is only used for Windows as the media is all streamed from the network.

I built it myself and it has run perfectly for about 1 year before the shutdowns began. It's been happening regularly now for a few months and seems to be getting more frequent. But it's inconsistent – sometimes it will run for a week without incident and then die twice in one evening, though now it seems to crash within 20 minutes every time I use it.

[logifuse]

What are the chipset heatsinks like heatwise? I've had similar issues related to that before.

How about the RAM? I've had some that was running at higher voltage than recommended (I didn't overclock it, it was just what the BIOS chose), & it would cause crashes.

Having said all that, I think it sounds like a capacitor issue with the board.

Justin

[TiggerK]

Yeah, it sounds like overheating from initial description, but the fact that it'll sometimes work for ages means likely not heat related. I would have said power supply but you said you've changed it (although replacement is same brand... hmm, any other brands you could test with??)

I expect Justin is on the money with a faulty Mainboard capacitor. Problem is, only way to find out is to replace it!!

Cheers
TiggerK

[greedo]

Yeah, it sounds like overheating from initial description, but the fact that it'll sometimes work for ages means likely not heat related. I would have said power supply but you said you've changed it (although replacement is same brand... hmm, any other brands you could test with??)

I expect Justin is on the money with a faulty Mainboard capacitor. Problem is, only way to find out is to replace it!!

Cheers
TiggerK

Thanks both you guys for your responses.

re: PSU - the PSU is actually proprietary from the case manufacturer (Antec) and no other PSU will fit in the case.
There is definitely not overclocking going on from my end, but I will double check that no 'auto overclocking' stuff is happening.

@Logifuse
I hadn't thought of the heatsink on the chipset. That would certainly be a possibility since the symptoms scream 'overheating' but the CPU is almost certainly not overheating. I'm booting up to test the chipset sink right now.

thanks again, I'll see how I go

[Yknot]

Thanks both you guys for your responses.

re: PSU - the PSU is actually proprietary from the case manufacturer (Antec) and no other PSU will fit in the case.
There is definitely not overclocking going on from my end, but I will double check that no 'auto overclocking' stuff is happening.

@Logifuse
I hadn't thought of the heatsink on the chipset. That would certainly be a possibility since the symptoms scream 'overheating' but the CPU is almost certainly not overheating. I'm booting up to test the chipset sink right now.

thanks again, I'll see how I go

Hi Greedo...

A bit late for a reply I know, but I had the same issue some time ago. Turned out to be my PSU was underpowered. Replaced with a higher wattage and never happened again. Hope it helps.

[TiggerK]

Was the old one underpowered or maybe just faulty??

Anyway, be nice if greedo could follow up with what happened......?? Always good for others having issues to see the final resolution.