Computer restarts after shutdown

[DarkIceJack]

The title says it all, whenever i shut down the computer after about 5 seconds the computer just restarts by its self
Everything apart from the PSU and GPU are new, and i was wanting to know your thoughts on what the problem could be.

Computer Specs:
MoBo: ASUS P5P41D ATX
CPU: Intel Core2 Quad Q8400 2.66GHz
GPU: Nvidia Geforce 9600GT 1GB
RAM: 4GB DDR2
PSU: 650W
HD: Western Digital IDE drive 120GB, Western Digital SATA 650GB
OS: Microsoft Windows 7 64-Bit Home Premium

[city14]

A lot of computer problems occurring right now...

Hmm, well you could double check that your power connections are going to the right place. There could be something there. That's where I would start.

If that doesn't work, then look at reseating everything. And then I would be out of ideas right now... Other then drastic measures.

[Dives]

Sounds like its unable to POST. Is it making any beeping?

If not, it may just be unstable bios settings and changing them back to default may do the trick.To do it, you'll have to open up your computer and reset the jumper. I've found your motherboard manual online.
http://www.iusermanual.com/motherboard/ ... manual.htm

Just follow the instructions under the "1.9 jumpers" section.

Edit: hold on, if you mean your computer won't stay off after you shut it down, ignore this post.

[Dionysos]

I suppose everything else works? Check whether the wires going from the reset and shut off buttons are connected to the correct pins on the motherboard. You can also try flashing your bios to the latest version or resetting the bios settings to default.

[city14]

Let me just try to clarify... Is it working fine, then after you shut it down, it just comes back on?

[DarkIceJack]

Sounds like its unable to POST. Is it making any beeping?

If not, it may just be unstable bios settings and changing them back to default may do the trick.To do it, you'll have to open up your computer and reset the jumper. I've found your motherboard manual online.
http://www.iusermanual.com/motherboard/ ... manual.htm

Just follow the instructions under the "1.9 jumpers" section.

Edit: hold on, if you mean your computer won't stay off after you shut it down, ignore this post.

Have now fixed the problem, I reset the bios and the computer stays shutdown (WOOHOO )