CPU usage high after upgrade.

Problem: My CPU usage is waaayyyyyy higher than it use to be.

Here's the history, I got a new video card and heatsink/fan, and upgraded my RAM with the exact same kind I've already had.
I had to take off my mobo to put on the brackets for the new heatsink/fan for my CPU. I was careful cleaning off the old thermal paste, etc etc. I changed my 4870x2 ATI card for a new Nvidia 680. and my ram from 6gb to 12.

I forgot to uninstall the old drivers when I put in the new card, and when I turned it back on, my cpu was stuggling so hard at 100% when I first started up, but my temps aren't even going above 50. I've checked to make sure it was reading all my stuff right, I uninstalled the ATI drivers and used drive fusion to remove the left overs, and installed the new Nvidia drivers.

But still my CPU usage is running so much higher. All my start up programs use to be nothing to my CPU. Now I have to turn pretty much everything and I will still idle around 50%. I will try to play WoW and I might get like 5fps, but my CPU doesn't even max out then, everything seems to be using a lot more CPU or something. I really don't know. I've tried so many things.
I've tried taking the RAM back out, I've double checked to make sure I put my heatsink/fan on correctly, I've tried unplugging my usbs, and my new monitor's HDMI, but nothing, I've scanned to make sure it wasn't a virus, I've checked to make sure there are no extra processes for the most part. I've double checked to make sure the ATI drivers are gone, I've reinstalled my video drivers a few times, I've made sure my bios and chipset drivers are up to date, I've even tried clearing my CMOS and still nothing.

The only progress I've made in solving this is that my DPC latency is very high.
I really really need to fix this. Please help me. :\
Specs:
i7 920 intel CPU
12GB DDR3 RAM
Foxconn Renaissance Mobo
Fatality Soundblaster soundcard

Info:
http://img202.imageshack.us/img202/7189/86753109.jpg