System will not shut down, only restarts

[EnderW]

A couple weeks ago, my system started doing this thing where it won't shutdown, only restart. This all started after I moved it into a new case and it also forgot my BIOS settings a couple of times. It didn't do this restarting this when I built it about a month ago.

Specs:
Asus P5Q Deluxe
Intel Q9450
2 x 2GB Corsair Dominator
ATI 4870
VelociRaptor
Corsair HX620W
Windows Vista Ultimate x64

I've tried different video cards, different PSUs, fresh install of Windows, loading BIOS defaults - nothing changes it. Also in my BIOS settings, all the "wake from ___" options are disabled.

 

[Dangman]

- Did you clear the CMOS?
- Did you reassemble the PC outside of the case on the offchance that the case may be the cause of the problems?
- Just to rule this out:
Download Memtest+ V.170, unzip it, burn the ISO file to a CD, and then boot from it, just like you would do with the XP install CD. Let Memtest+ run for at least three hours on each stick of RAM separately. Go for a full 24 hours if you want to be completely sure that the RAM is not a problem. If you start seeing errors, than your RAM is bad.
- And to rule this out:
Google, download, burn the ISO file to a CD, and boot from Drive Fitness Test to see if the hard drive is bad or not.

 

[EnderW]

- Did you clear the CMOS?
- Did you reassemble the PC outside of the case on the offchance that the case may be the cause of the problems?
- Just to rule this out:
Download Memtest+ V.170, unzip it, burn the ISO file to a CD, and then boot from it, just like you would do with the XP install CD. Let Memtest+ run for at least three hours on each stick of RAM separately. Go for a full 24 hours if you want to be completely sure that the RAM is not a problem. If you start seeing errors, than your RAM is bad.
- And to rule this out:
Google, download, burn the ISO file to a CD, and boot from Drive Fitness Test to see if the hard drive is bad or not.

someone on another forum mention the case possibly shorting out, I took it out of the case and works fine now

only things I noticed when I put it in the case were the video and sound cards seemed to be slightly out of alignment with the case, like they were in at an angle, but it was very slight, just about 1mm, and I just pushed them over and screwed them in
also, the I/O shield for this MB is kinda weird, it's thick with padding, never seen that before
about to put the system in my main case and see what happens - this was in a secondary case I hadn't used before