I resently purchased a Dell vostro 460 and ran into a problem with an expansion card.
The card was a pci-e x1 card that would give me a 25 pin parallel port so I could us my old printer, windows 7 pro installed without problem but when i tried to shutdown the computer would shutdown for about 2 seconds then restart.
I disable restart when windows encounter an error in hopes of seeing a bsod nothing, checked the power settings, made sure the shutdown button was actually set to shutdown aswell checked event viewer nothing. But it ended up being the adapter card, because after i removed it the problem disappeared.
Dell only solution was a format which didn't help, going to try a parallel to usb adapter cable today and hope for the best.
Any suggestions on how I could get the card to work without the computer restarting would be appreciated, never thought windows 7 would play nice with the hardware at least not without giving me a warning at least.