Need help with having Windows use both cores of my Pentium D

Hi everyone!

I never tried to fix this before, but Windows (XP Pro w/ SP2 & all updates) only shows one core from my Pentium D 805.

I checked Task Manager and have One CPU per graph, but only shows one graph. Also, CPU-Z has the Processor Selection drop down grayed out. I also know that I am only using one core because I use VMware and the virtual machines only use one processor, but my physical processor can go up to 100% instead of 50%.

I have the latest BIOS, ACPI is enabled, and POST shows "Count: 2" for
my CPU. Device Manager shows "ACPI Multiprocessor PC" and even shows 2 processors of "Intel(R) Pentium(R) D CPU 2.66GHz"!

I have also tried to set NUMPROC=2 in boot.ini, but that didn't work. I would like to keep this installation, and not reinstall it, but I will try later to install a fresh copy in another partition to see if that has the same problem.

I've searched on the internet and on these forums for a possible solution, but couldn't find one. I appreciate any help you can give me! Thanks.