computer doesn't power down

[Guest]

I recently built a "new" computer. The problem I'm having is the system won't power down. It simply hangs and stays on. I have to shut it down with the power button on front of the case. At first I thought it might be a vista problem, but I tried a couple of linux live cds and I have the same problem. The linux systems halt, ie: the sytem message says the OS has shutdown, but the computer doesn't. I've double checked all the connections and they appear to be correct. I'm perplexed.
Here's my system
Gigabyte EP43-DS3L mobo
Core2Duo E6420
BFG nvidia 7950 GT
2 gigs corsair xms2 800Mhz
500w coolermaster PSU
maxtor diamond 160G
current OS Vista

 

[nutbag]

Problem solved. I needed to update the bios. I used the gigabyte @bios program and it worked like a charm, despite the warnings I read. So anyone with this board that is having issues, update your bios. It seems odd that a a new board won't auto shutdown. My board shipped with bios version F2 and I updated to F7. Hope this helps someone else.