hunterbob33 :
Windows 7 Home Premium and I did originally have a quad core in the old build that my current hard drive was originally in but all of the other hardware is completely new in my current rig.
That sounds something that could be related. You did a fresh install of Windows right?
But, even if you did, usually Windows only creates the new partion for WIndows itself, and uses the old system partition if the disk had one. It's a small, usually 100 MB partition which can be seen from "disk management". It contains bootloader and some other stuff. It's not mounted so that it doesn't have a drive letter assigned.
My hunch would be, that something in the old partition has something, driver code or setting, that's limiting the number of cores to 4 like it was in the previous build it was created in. The setting is the same as the mentioned msconfig edits.
You can rewrite most of it by going to Windows recovery mode, started by booting and pressing F8, then go to recovery console.
bootrec /rebuildbcd
But I'm not sure it would help. It's worth a try though.
Another try. Go to device manager and click action ->scan new hardware.
Hmmm...oh by the way, you have installed the latest service pack and all upgrades right? Because I think support for FX series came with some hotfix.