Vista 64 only shows 2 cores on a Quad 6700?

I swapped out my E6600 over the weekend for my Q6700 and Vista task manager only showed 2 cores in Task Manager. I wanted a clean install of Vista anyway, so I reformatted and reinstalled and still only 2 cores show up in Task Manager. I made sure the option to show one graph for each CPU was checked. Has anyone ele encountered this? I tried Google to no avail. Bios reports a Quad, as does the General Tab under System Properties.

What version of vista are you using?

if you right click a process in the task manager and select affinity, does it show you the 4 cores?

It's ur mobo, I own same mobo u have before. you need to go into bios and tell it to enable 2 more cores.

Sorry, I am running Vista Ultimate 64 bit. I'll double check the bios, thanks for the info.