Computer won't power up at all

[fray_bentos]

Just added a new hard drive to my desktop (on a laptop now) and now the machine won't respond at all, power button does nothing.

I had to remove an old drive which had stopped working and change the IDE cables round and add the new drive and now as I said it simply won't respond. Part of the power appears to be ok as one of the pci cards has a light which is on. Starting with the simplest thing, how can i start it without a power button? - If the button and its connection are fine, what are the likely problems which would make it completely unresponsive? Something physically damaged on the motherboard perhaps, or static?

As you can tell, I'm not that knowledgable so I'm at a loss what to do, so any suggestions would be gratefully appreciated. Thanks.
mods: having now read the sticky perhaps I should have put this in hardware, if appropriate move it please.

[vinnyT]

Check that you have not dis-lodged any cables on the mobo. Checked that you haven't unseated your cpu, or ram sticks.

If there was a problem with the hdrive, then you would most likely see an invalid system disk error onscreen, so this would suggest that the prob is deeper than the hdrive.

[fray_bentos]

I checked the cabling i thought could have been affected and the ram but didnt check the cpu. As you say, if it was just the drive then it would atleast power up but its just completely unresponsive. So i need to check the cpu and double check the cabling, any other ideas?

[Viper81]

To try and get the system powering up again, I'd uplug all the IDE drives first. Then unplug the mains power cable to the PSU and wait 10 secs before re-connecting it. Then try powering it on and cross your fingers!

[emul8]

Sounds like a PSU problem

You can easily test your PSU by disconnecting all the power cables from the motherboard and peripherals then take the 20/24 pin plug and short the green wire and a black wire together using a piece of wire or metal clip like a paper clip or something,
If it fires up it should be OK if it does not fire up then it may have failed
I would also check that you have not dislodged any of the front panel cables namely the on off cable to the motherboard

[fray_bentos]

Ok, I'll unplug all the drives and try that. emul8, I'm not sure I want to short the psu, I do need to test that though as it seems that might be the problem. I checked the connection of the on/off switch and it was ok, I'm just surprised there is no easier way to power on without the power button.

I'll try this all later tonight.

[emul8]

I'm just surprised there is no easier way to power on without the power button.

There is an easer way but that would require a PSU tester.

Don't worry you are only doing what the motherboard does and that is connect the green to black!

Have a look here

[peterb]

My first thought is that you have accidentally dislodged the connection from te front panel switch to the mobo - very easy to do when you are re-arranging wiring. One other thing - if the PSU has an external power switch on the back (near where the mains connector is located) check that you haven't cought that and switched it off unknowingly.

[Disturbedguy]

I would try a new power supply.

...Bert

Did you actually read any of the thread?

Part of the power appears to be ok as one of the pci cards has a light which is on

I dont think its a PSU problem as the person is getting power to his PCI card as mentioned.

Is there anyway you can check the cables that lead to the Power Button, maybe one of them has come lose..or maybe the connector for the power button on the motherboard isnt on properly and it just looks like it is, I have had this before..very annoying.

[fray_bentos]

Well, good news, it's working again. I got some time tonight, disconnected nearly everything, made sure everthing was seated correctly and reconnected it all (one drive at a time).

So I can only assume that something was loose, although I'm not sure what as I thought I'd tried all the connections when it first broke. The new drive I added (which was unplugged) is completely broken it seems as when it's plugged in the machine again doesn't power. Very annoying to lose another drive, especially as it was meant to be the drive to which I backed up my data.

Thanks to all who helped, I was just going to assume it had gone and abandon it as it is an old machine but the suggestions made me try to fix it and I'm very glad I did.

[vinnyT]

Well done!

[Disturbedguy]

Good to hear that everything is ok mate.

[dangel]

I dont think its a PSU problem as the person is getting power to his PCI card as mentioned.

As a sidenote - PSU's can die in a number of ways, one of them is to leave the motherboard powered but unable to fully start the machine. I've fixed several machines stuck in this mode.