I ran across a vid on Youtube, and some guy recommended a program that unparks your cores by modifying registry settings. Here's a link to the video...
http://www.youtube.com/watch?v=eyo6H3W-vu8
And here's a link to the website if you wanna read up on the program, access the source code, or download the actual program.
http://www.coderbag.com/Programming-C/Disable-CPU-Core-Parking-Utility
The guy in the Youtube vid said he experienced an increase of 10-15 fps in cpu intensive games. Feel free to share your thoughts.