New System stopped working (turned on, but then shut off for good after a minute or so)

[Startled Armadillo]

I just finished putting together my new system. here are the specs:

Gigabyte K8N Ultra-SLI
AMD 64 3000+
Antec NeoPower 480 PSU
MSI GeForce 6600GT
2x512MB Kingston

I installed the motherboard, CPU w/ stock heatsink/fan, memory, video card, and PSU into the case. after making sure all the wires were connected properly, I plugged it in and turned it on. The system started right up, made a single beep right away, and then started loading everything. it detected all of the memory without any problems, however it listed the processor speed as 200MHz. Since I hadn't installed a hard drive yet, it stopped when it had gone as far as it could.

So, I hit the power switch to turn off the computer, and then restarted it so that I could go into the BIOS. Everything started off normal again, but once I got into the BIOS control screen, the computer shut itself off. I have not been able to get the computer to turn back on. When I turn on the PSU, if I have the keyboard and mouse hooked up they light up so I know that the system is getting power.

I tried taking the motherboard out and setting it up on a piece of cardboard w/ only the PSU, Memory, and video card installed, just in case something in the case was shorting it out, but this didn't help.

Any help that anyone could give me would be much appreciated...basically, the computer worked, then it turned off without me even touching anything, and now it won't turn back on. I have a bad feeling I'm going to need to RMA something, I'm just not sure how to go about figuring out what the problem is.

Thanks,
Chris

 

[amdskip]

Reseat the memory if you have not done so already.

 

[Startled Armadillo]

yeah, i tried reseating the memory...doesn't help. I don't know what to do to figure out where the problem is.

 

[sisq0kidd]

Just a guess, but I assume your motherboard shorted some how... Try clearing the cmos...

 

[Startled Armadillo]

i tried clearing cmos, but still nothing. i even took the battery out and left it out all night.

 

[Biggerhammer]

How is the motherboard installed- all proper spacers, screws etc?

 

[Startled Armadillo]

well, when it was working it was installed properly in the case. but then it turned off and wouldn't turn back on again, so i took the Motherboard back out of case and currently it is sitting on a cardboard box w, only the cpu, heatsink/fan, video card, and memory installed. still won' start back up...

 

[Startled Armadillo]

could it be that something happened to the motherboard? i really don't know where to go from here. what could go wrong that would shut a computer off the 2nd time it turns on, and then make it so the computer is dead and won't turn on again (fans aren't even turning anymore)?

 

[Biggerhammer]

A PSU failure might toast the MB, though it would be sort of bizarre to have it do so with no change in the system first. Do you have a decent surge suppressor? I'm guessing here.

 

[Startled Armadillo]

the surge protector isn't the problem, and the PSU is brand new and seems to be fine as well (i might bring a voltmeter home from work today to check it out)

 

[Pr0d1gy]

Originally posted by: Startled Armadillo
the surge protector isn't the problem, and the PSU is brand new and seems to be fine as well (i might bring a voltmeter home from work today to check it out)

Yeah i would definitely bring it home & check out the PSU. If that is fine, then I would look at the mobo or CPU for RMA.

 

[Startled Armadillo]

assuming the power supply is fine (i haven't had the chance to check it yet...i have to wait til i get home from work), how would i tell whether the problem lies with the mobo or the CPU?

With a bad CPU and a good motherboard, wouldn't the system at least attempt to start up, ie fans would turn on (case fans and psu fans), followed by the case speaker giving a set of error beeps?

when i hit the power button, absolutely nothing happens. so would this mean that the mobo is the problem and I should RMA that? is it likely for something in the motherboard to just break a minute or two after being powered up for the second time?

ALSO, i've never checked a PSU with a voltmeter before...what/how should I test and what should I be looking for? could anyone give me advice on how to go about doing this, or point me in the direction of a good website that could lead me through it?

 

[Startled Armadillo]

ok, i've got a voltmeter and i'm looking at the power supply now. With nothing connected to the motherboard (just looking at the free cable), the 5VSB pin is a steady 5.03V, so that's good. With the PSU connected to the mobo, the green wire (power on) also reads a steady 5.03V. Pressing the power button (or simply shorting the power button connectors with a screwdriver) causes the reading at the green wire to reduce to zero, but nothing happens (psu doesn't turn on, no fans move, everything is quiet).

What else (and how) do I need to check with my voltmeter to determine whether the problem is with the mobo or PSU?

Thanks

 

[Startled Armadillo]

I went out and bought a power supply tester today, and when I plug the PSU into the tester, the only LED that comes on is the +5VSB. All of the other LEDs stay off and the power supply does not turn on.

So does this mean the power supply is bad and I should RMA it? does a failing power supply account for the problem I had with my new system (computer shuts off after about a minute and nothing will make it turn back on again)? There were no sounds or strange smells when the computer shut off, which is why I didn't suspect the PSU at first.

What are the odds that a power supply failing like this damaged my new mobo/cpu/memory/video card? I really hope that didn't happen...

Thanks,
Chris

 

[waitman]

So does this mean the power supply is bad and I should RMA it? does a failing power supply account for the problem I had with my new system (computer shuts off after about a minute and nothing will make it turn back on again)?

Yes

What are the odds that a power supply failing like this damaged my new mobo/cpu/memory/video card? I really hope that didn't happen..

I'd try a different power supply first, I have had the same thing happen to me. If you are only getting voltage to the +5VSB with a tester, you have a problem, either the psu or the tester. From what you describe my guess is the PSU.

 

[imported_jzimo]

From what I understand when you press the power button nothing happens? No fans spin, just nothing. If that is the case it is powersupply. I shorted out one of my motherboards and all the fans turned on and hard drive responded but no display. If your getting nothnig its the powersupply.

 

[Startled Armadillo]

ok, well i guess i will RMA the PSU to newegg. once i get the new one, hopefully everything will work when i hook it all back up. it's pretty frustrating to have all the parts for a new system and have them just sitting there unusable because of something like this.


is it very common for power supplies to fail so quickly?