Motherboard or Power supply?

[Pc Converge]

I received an HP Pavilion Elite from a customer of mine. It wasn't booting up and was showing an error "Reboot and select proper media device or insert a select media device and press any key" error.

Thought it was the hard drive, so I removed it and attached it to an external case and seems to function fine. I also performed a chkdsk on it, and no problems there.

I return it to the original computer (HP Elite), and it boots fine. Hmmm, must've been a loose connection, right? Wait, a BSOD flashed a 0X000000F4 error.

I take out the hard drive and test another one. It doesn't boot. I try to boot multiple live cd's (ubcd4win, erd commander, hiren's), and the weird thing is, it only boots from these cds maybe every 10 or so boots, usually if I leave it unplugged from the strip for multiple minutes. Its usually stuck on the first bios screen where it shows "esc for bootup device, F9 for diagnostic, etc., and sometimes won't do anything after.

I removed all but 1 RAM module from mobo, the hdd, one Dvd-rom at a time, removed the cmos battery, and it nothing seems to help. I don't have an extra power supply to test if that's the issue, but I will be testing the outputs to ensure they are all correct voltages.

My educated guess is that the motherboard is bad and needs to be replaced. But, there is still a possibility that the PSU is causing the problems too, which I won't know till tomorrow because its too late to buy a new multimeter, because mine is crap

Any suggestions would be greatly appreciated!

Thanks in advance,
Vince
Pc Converge
San Francisco, CA

 

[TLE]

Ummm, try putting in a known good PSU?

 

[iptech]

I had a similar problem last week, my initial suspicion was a failed hard disk, but when I tested the PSU it showed one of the 5v outputs to be fluctuating slightly. The hard disk tested fine and the problem was cured with a new PSU.

Rather than use a multimeter, I would invest in a dedicated quality PSU tester, it looks more professional and provides a basic diagnostic output that a customer can understand.

 

[wimwauters]

I don't have an extra power supply to test if that's the issue, but I will be testing the outputs to ensure they are all correct voltages.

My educated guess is that the motherboard is bad and needs to be replaced. But, there is still a possibility that the PSU is causing the problems too, which I won't know till tomorrow because its too late to buy a new multimeter, because mine is crap

How is your multimeter being crap? There's not much you can do with multimeters or power supply testers, because none of these put any serious load on the PSU.

If you are lucky, the faulty PSU might fail or show errors at low load, but normally they will only show errors when they are put under pressure, just like people

If the power supply is easier/cheaper to get than the motherboard, I would try that first. And ATX powers supplies are cheap these days
Surely this board takes standard powersupply plugs: it might not fit in the computer case, but you are only testing the motherboard.

 

[Pc Converge]

The multimeter keeps showing different outputs for the power cord, and the auto is just annoying. Got it for free, but now I'm realizing why lol

I'll go ahead and swap the psu and see if thats the culprit. Thanks for the advise guys I'll keep you informed of the situation.

 

[JD1248]

Have you checked the mobo for any swollen capacitors. The problem your describing certainly could be a case of a bad cap. If you don't know what to look for, go to badcaps.net.