Fail to POST

[MrCoffee]

a friends HP desktop PC has some problems. Apparently It powered off during gameplay and now it will POST at the first attempt after a while left cold but it BSOD very early in the boot process and shuts it self off. The BSOD is only up for a split second, no way to tell what it says, not much more than a blue flash.
It then refuses to POST until its been left cold for x amount of time (hours maybe), all that happens is the fans power up (CPU & Chassis fans, not sure about PSU) - keyboard doesn't respond, no signal to the monitor.

I have some ideas myself what it might be but second opinions welcome.

Edit: BTW, its a P4 system, about 4 years old. Small crappy PSU - voltages check out but not sure if the fan is spinning.

 

[Ste]

Id switch out the RAM First..

Then the PSU if it still fails with new RAM.

 

[MrCoffee]

I'm very much leaning toward thinking its the PSU - anyone seen these symptoms before? could it be the CMOS battery?

 

[Ste]

A failed CMOS battery would not cause this.

All that would happen if the cmos battery was dead, is no CMOS settings would be retained and the time in windows would be wrong..

 

[Jorsoft]

Id switch out the RAM First..

Then the PSU if it still fails with new RAM.

That's what I'd do too. The BSOD makes me suspect ram first, psu second.

 

[MrCoffee]

OK, i'll give that a go.

I didn't think RAM because there are no beeps and its odd that it only POSTs after being left cold for a while. There are 2 sticks so I'll run with 1 and see if I can get memtest86 fired up.

 

[Ste]

Don't rely on the motherboard beep system to help you trouble shoot.

If theres one thing I learned from my 7 AM highschool A+ Class is that motherboards are not all that reliable when it comes to getting the beeps codes to the corresponding problem correct.

 

[SYL\X/3K]

Small crappy PSU

theres the problem, 4 years not bad for a crappy PSU to last

 

[Nitestick]

stick to the usual elimination process and you'll find it. first though i would clean out the HSF and re-seat it.