Sony VaioPCG-6J1M win't shutdown / restarts

As I'm a regular lurker, I hope you guys don't mind if I ask this question here. (Posted elsewhere)

Machine has just been restored, and when asked to shutdown, it restarts.

I've googled, and have had no luck so far.

Has anyone got any ideas?

I've tried these sites
Windows XP restarts when you try to shut down your computer
Windows XP Shutdown Troubleshooter

I've already use 'My Vaio' to update the machine.

I've applied XP SP3

No joy...

 

The reboot on errors check box has been cleared.

 

The reboot on errors check box has been cleared, but the problem persists.

The BIOS is the most basic BIOS I've ever seen, about the only thing it allows you to change is the boot order of devices.

That's weird. I looked but didn't see any way to enter into an type of advanced settings for the BIOS.

There is a BIOS update, but it's for a power management issue, which is seemingly unrelated, but I'm going to give it a shot. I hate BIOS updates....