Computer will not power up

[aa1312]

Hello. Let me give you all the specifics that are involved.

A friend wanted me to look at a pc for spyware, and possible trojans, so he brought the entire case over. While unplugging all of the devices, I was told that the face plate came off, which ripped the Power SW cable from the power button to the motherboard.

I had an extra pc case that I could give him to have to replace since his tower was in very bad shape to begin with. I dis-assembled the machine, and put all the old parts from the old tower to the new one, all except the add on cards, and drives.

All that is connected so far to the board are:

Power supply
Stick of ram
Processor & CPU
Video Card
Power SW cable
(all verified to work)

When I fire up the machine to turn it on, nothing happens. So I troubleshoot a little bit by making sure the Power SW cable is corrected in the right pins, and it appears to be so. I swapped power supplies ( that work), and no go. Tried replacing the battery on the board with a working one, and no go. Tried using a different memory stick, no go. Used a different processor (same bus speed) from a working machine, no go.

The fan on the back of the power supply will not even power up on this board, but will on other boards. The heatsinks' fan will not even start. I've exausted all of my resources, and I don't know if I should come to the conclusion that the board may have had a hardware failure from the departure of the tower from point A to point B.

Any ideas? Anything would be greatly appreciated, thank you.

[profdlp]

Try resetting the CMOS. What motherboard does he have?

You might also want to make sure that you didn't get one of the MB standoffs in the wrong place. While you've got the MB out to check that, I'd try hooking everything up and trying it outside the case.

Good luck. :)

[aa1312]

Here she is

http://www.jetway.com.tw/jetway/system/productshow2.asp?id=55&cd=c3&proname=N2PAP%2DUltra#show

I can recall resetting the CMOS jumper, but I will try again. Also, what are the pieces of hardware that "must" be present to actually fire up a power supply? Thanks again.

[profdlp]

Some PSU's will power up with nothing attached, though you need to short a couple pins on the big plug. Most need some sort of load on them, though often all it takes is a case fan or two.

Have you tried it outside the case yet?

[aa1312]

Just got done trying to power it up from outside the case. Same problem.

Something to add. When I hit the power switch on the tower, the PSU fan spins for about a millosecond, and then shuts off.

[aa1312]

Probably will end up replacing the board, or taking the board to a shop for them to investigate. Thanks for the help again.

[profdlp]

It doesn't happen quite so often these days, but older boards sometimes had a problem where as soon as you booted up it would shut right down due to a perceived CPU fan failure. This was due to the fact that the CPU fan hadn't had enough time to come up to speed before the BIOS panicked and cut the power.

I had an old Abit board like that. If I would keep trying to start the system, about one time in ten it would actually start up. The solution was an updated BIOS which had a delay built in to the process.