update the BIOS. thus it's reading it improperly (not recognizing it), Visit the motherboard's product support page, hit the downloads section, and install the latest BIOS from website your motherboard
MSConfig > Boot tab > Advanced Options > "Number of Processors" and exit MSConfig - restart
if still recognize you need install fres OS
um..... idk how to update the bios its really confusing and i checked the website and it says its compatible with my processor. and the ms config says only 2 cores when it should say 4. I was going to reinstall windows 7 but i dont have the dvd. do you know of an easy way t flash the bios? or if reinstalling the OS will fix it? I'd rather not have to do both if i don't have to.