PC used to reset unexpectedly but now can't even boot!

[redsix]

Hi,

 

I have recently been experiencing reset problems with the PC (custom Intel Dual Core 2.8GHz 2GB WinXP Home SP3 etc.) I use for audio production. After running the usual malware scans and driver updates, the system would still occasionally reset.

 

There is no blue screen or error report, and Windows only reports that it suspects a hardware/driver issue.

 

Having read a few threads this does sound like a power supply or temperature issue. I spent a while cleaning out the inside - removing the CPU fan and hoovering/wiping down all the exhaust fan dusts (all on my ESD mat with my ESD strap!).

 

After all this, the system is now powers off completely during mid boot and does not restart.

 

I'm thinking the power supply is totally screwed, but could it be anything else? Or has something maybe totally fried my PC ...? Please can someone help?

 

Thanks!

[Guest Wolfeymole]

Hoovering? mm very dodgy.

 

When you removed the CPU fan you didn't dislodge the heatsink by perchance did you, sometimes CPU fans can be a real arse to remove.

[redsix]

well ... i removed the whole fan/heatsink assembly before i saw the handy little fan clips (it's been a whhile since i installed the cpu and its fan!)

 

The heatsink also had a fair bit of dust, as did the intake fans. I didn't run the hoover over the motherboard if that's what you were thinking :)

 

the machine now gets thru hardware and memory checks and seems to switch itself off when trying to load windows, after shifting the fan speeds around a bit :confused: it all seems a bit wrong now ...

[Guest Wolfeymole]

If you removed the CPU fan AND heatsink did you apply thermal paste to the CPU when repositioning the heatsink?

[redsix]

hmm ... there was paste on there from the original install - you think I should add more having removed and replaced it? dang i didn't do that :( admittedly it didn't look like the most generous layer of paste ... do you think it's just overheating then?

[Guest Wolfeymole]

If you have slapped the heatsink back on the cpu without a blob of thermal paste the heat may have took the board out, either that or the PSU is goosed.

[Plastic Nev]

Hi, All you can do now is remove all the old paste, replace it with some new and try again, but the fact it isn't loading and seems to me it isn't getting past the BIOS, it may well have done in the CPU chip, or even the board.

Nev.

[redsix]

ach noo :( that sounds bad ... i guess i didn't have my hardware head on there - these chips get hot. i'm guessing the board is ok if it gets thru its checks and tries to launch the OS ...

 

so do you think i should try adding some paste, or go straight for a psu replacement? if none of that works, then it's new motherboard and cpu time i guess :(

[redsix]

(sorry nev - i think i was typing during your last post!) it basically sounds like either my psu is dead and/or the chip's overheating when it has to do a bit more work. I'll try the paste route then start building from the ground up. With a new mobo and chip, will my old system drive be ok? or should i do a clean windows install too?

[Plastic Nev]

Hi again. I was working and talking with Wolfey when this first came up, as I said it seems that it is getting to the first checks OK but not getting past the BIOS from there.

So there are a few possibilities as to what could now be not working, however the CPU chip is only one of them, the hard drive comes into question as that is next in the sequence when the BIOS asks for an operating system, which of course is stored on the hard drive. If that has died then nothing else can happen also.

If it is at all possible to swap the drive into another computer to check it it may be an idea if you have access to another machine similar. OK Windows will refuse to open but it will at least get that far, which it isn't doing now, but that will prove the drive is OK or not. There is also the chance that other hardware may be duff, but at the moment, I don't think there is much wrong with the power supply as it is providing power for the initial stuff.

Nev.

[redsix]

ok - by way of fault finding i'll try the system drive in another machine tonight - do u mean as boot, or as a secondary drive to see if it's alive? is it feasible that a hdd can be broken when accessing only part of the disk (e.g. the system files) ...?

 

the boot sequence seems to start loading windows, system files etc. before dying. I've seen a dead [ide] hdd before on a previous machine, and this was reported by the bios as it wasn't able to communicate with the drive. from the symptoms i'm seeing, the drive is not totally dead, but i guess it could be partially sick.

[redsix]

Hi all - i think i have a clearer picture of this issue now. i applied some more thermal paste to the heat sink and removed a couple of cards and got the machine to boot. I then fired up the sensor modules and drove the fans harder, and the system sat idling ok at around 47C. Then I added the cards back in and the system idled at about 55C. Whenever the PC works harder (i mean web browsing, not audio processing) the temperature shoots up to 64C and the fans struggle to get the temp down. This is all with the case open! I'm thinking the system is running too hot :S

 

The system lives in this antec rackmount unit, which has disappointed me from day 1. I had to remove a chassis fan to fit the cpu fan (my akasa heat pipe or even the standard intel jobbie), and the psu fan doesn't turn at all! This means half the expected intake/outtake isn't even happening, which may explain the overheating. I think it's time to get a new case! Any advice is greatly appreciated :)

[Tootech]

Whenever the PC works harder (i mean web browsing, not audio processing) the temperature shoots up to 64C and the fans struggle to get the temp down

 

That shouldn't happen.

 

Is it a Core 2 Duo 2.8 GHz E7400 you have?

 

The standard heatsink and fan should keep that CPU cool well beyond anything you are doing. If that is your CPU it runs cool anyway, and Core 2's are pretty energy efficient - read that as creating less heat than previous Intel CPU's.

 

Check the idle temp from the BIOS to cross reference your readings.

 

Remove the heatsink/fan assembly, clean it perfectly, clean the top of the CPU perfectly, apply a dab of new paste, reassemble and re check the temps.

 

Nail varnish remover will shift the old paste if it is solid.

 

Apply paste like this

 

http://www.circuitremix.com/images/124/apply_2.jpg

 

the psu fan doesn't turn at all

 

Is there any air being vented from the back of the PSU?

 

If not, I'd guess there is a fault with your PSU - does it have a make/model number, and a wattage rating?

Edited July 28, 2009 by Tootech

[redsix]

Hi

 

I cleaned the surfaces of the die and the heatsink with timclean and reapplied the paste.

 

The CPU is an Intel Pentium D 2.8GHz (from the BIOS, string) - I can't recall the precise variant, but I think it's an older chip than the E7400. The BIOS indicates the same idling tempearture of 55C to 59C (case open). Is this cool? I was thinking that 60C+ was getting a bit hot.

 

Looking inside the PSU grille (Antec SP-450P), the fan doesn't turn at all. I think the case is supposed to draw intake through the front and expel via the PSU at the rear. The case has two further exhaust ports (rear and side). I have only one equipped with a fan because with a second fan installed I can't fit the CPU fan/heatsink assembly into the case (sounds daft, but many Antec cases seem to be configured like this). So basically the chassis has just one functioning fan through which air is expelled.

 

Do we still think this is a heating problem? The symptoms are very similar to a broken cpu fan i had in an old P3 machine years ago. The machine has never reset when idling since I cleaned the heatsink and reapplied the paste; only when it gets working a bit harder.