Troubleshooting a Dell Precision Machine After a Power Outage

[-Job-]

Great, i get home from work and find my fairly expensive dell precision machine, which i use as a web server, in some state. All three fans spinning very loudly at full power like a jet engine and the computer completely dead.
When i restart the computer no characters are printed, the monitor doesn't even get off standby, no error/beep codes, nothing at all save for the insanely loud noise of the fans.
It's not the memory nor any external component, and everything smells fine inside the machine (i.e. nothing burnt).
This might have been caused by a power outage, judging from the blinking of my alarm clock, even though i have an expensive APC battery backup plugged into a surge protector.
It sounds like a power supply problem, but before i throw any more money into this system i'd like to know if anyone has had a similar case.

 

[chroot]

Take a voltmeter to it and find out.

- Warren

 

[turbo]

In particular, remove the power supply (takes a couple of minutes) and verify that it is delivering the voltages specced. I don't like to test these "in situ" in case there are unresolved problems that may cause further damage. I had an office in a building that routinely experienced under-voltage and voltage spikes, and it's no fun when you lose an on-board drive controller to that kind of crap, so do a component-level check to make sure the power supply is OK before proceeding.

 

[-Job-]

There's voltage being delivered to the fans clearly, some leds light up, and i measured some voltage reaching the hard drive power outlets. Though i don't know what the power supply's specs are supposed to be. It's beginning to sound like the motherboard is gone.
The motherboard is supposed to bring the fans down. The fans always start at full speed when the machine is first turned on. So the problem is that the mechanism for turning them off isn't activating.
It could be an internal component such as the network card, which happens to be onboard.
Unbelievable.

 

[turbo]

OK, you have schematics (I hope) showing what your power supply needs to be delivering. On most power supplies, there will be an adhesive label showing what these voltages are. First make sure that your power supply is OK, then proceed from there.

 

[-Job-]

The voltages are 5 and 12 volts if I'm reading it correctly. I've confirmed that 12 volts is being delivered, although I'm not much of an electrical engineer.

 

[turbo]

That is pretty much standard for a US power supply in a PC. It looks like your power supply is OK, and it's time to wander down the food-chain.

 

[-Job-]

I recently bought the APC BackUPS too and they had a guarantee that they would refund up to $2000 for any electrical damage to any equipment connected to their device. It's probably just a joke/scam anyway but i'll look into it.

 

[Integral]

Do a search on ATX to find the specs for your power supply. Becareful about checking voltages with no load on the PS. ATX power supplies need a load to operate correctly. I am not sure what load is needed.

Last year I fought a similar problem for several months, replaced the power suppy, and mother board and the problem remained, it turned out to be a bad stick of memory. The memory seemed to work fine, it just brought the system to its knees everynow and then.

 

[-Job-]

There actually is an error code which indicates a "possible VRM 0 failure". Apparently a failure in the component powering the first processor, so a motherboard failure. Dell is sending me a new motherboard covered under the warranty. So that's not so bad.