Dual Xeon's, how to tell if they're running.

Hi folks,

Nothing too exciting here, just that I have an old Dell Precision 650 workstation, with Dual 2.8 GHz Prestonia Xeon's, and I can't really figure out a way to tell if both CPU's are running. I'm running Windows XP Home Edition, though with SP2. I know it's a dinosaur, but for a PC I got for free it's great for watching movies and network storage.

It doesn't seem to be that either of the processors are dead, as I've successfully ran the computer on each processor by itself, having removed the VRM and the second chip. Hyperthreading (though listed as not being supported on intel's website) is enabled, and CPU-z lists the computer as having 1 CPU - 1 Thread - 2 Logical Cores.
http://valid.canardpc.com/show_oc.php?id=2084886

Hopefully I'm not I think I'm going to end up doing a clean install of Windows for the heck of it, but I was wondering if anyone had any suggestions for diagnosing what might be wrong.

Thanks in advance.