I have a user in a remote office that tells me his machine is totally unresponsive at the moment. He arrived in the office to find his UPS beeping in some way, and there was other evidence of a power outage--clocks blinking, that kind of thing. Unfortunately, when trying to power up his machine, nothing happens. The machine is a custom-built rig; no brand or model number. Opening the chassis, there are LEDs visibly on inside when the power supply is on and plugged in.

I was thinking that perhaps the power supply was blown as a result of a surge or something (the user's area has had serious storms recently) however being connected to a UPS would seem to prevent that. Otherwise though I'm not sure what might be going on since the machine doesn't even post.

Any ideas? Thanks!

Edit: I've instructed the user to plug the machine directly to the wall, however the machine is still motionless following the power button. The fans don't even power up, however the same LEDs are still on as when plugged into the UPS. To me, if the machine can't even start the fans when the power button is pressed, it seems like it would be either the power supply or the motherboard; however, LEDs on the motherboard imply both that there's power going to the motherboard and that the motherboard is at least functional enough to run those LEDs.

Edit 2: After some trouble shooting over the phone, we managed to get the machine running--the motherboard has an onboard start button such that it can be powered on without a chassis switch, which in fact seems to be the difficulty. Motherboard start button is fine, chassis start button is "knackered." :)

Also, the machine's UPS is in fact surge-protecting. How likely/possible is it that the chassis' power switch was somehow damaged by a surge despite this? Perhaps it was faulty to begin with?


It really does sound like the power supply is knackered (technical term!). Even though it has enough power to light the LEDs, it can't produce enough to spin the fans or power anything else.

If I were you, I'd get another PC sent to that user ASAP and get the broken one sent back to you so you can either fix it or chuck it. Just think how much this person is worth to the company, and how much money you are potentially losing out on while this user is without their PC.

As an aside, just because it was plugged into a UPS, that doesn't necessarily protect it from surges - not all UPS' provide surge protection.


Attempt to disconnect power cord from computer for not less that 10 sec. And then connect back (maybe for test, directly to power outlet in wall to eliminate other causes) and attempt to switch on.

If not work, look like computre require repair.


Unplug the computer from the UPS and plug it directly into a wall outlet. If it powers up then you've got a UPS problem. If it doesn't then I'd say you've got a power supply problem.


In the end, it appears as if it's actually a problem with the power switch itself. I didn't know that was possible, practically speaking. The case is being RMAd, but sadly I'm not sure there's much to learn from this experience.

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