Degraded system performance - stuttering in games

I apologize if this is in the wrong section, I had no idea where to put this.

First thing first: Specs:
Intel Q8400 OC'ed to 3.5ghz (see below)
Thermaltake 750w PSU
AMD HIS 7770 Ghz-edition GPU
Mobo: MS-7345
Gaming hardrive: OCZ Agility-3 SSD
RAM: DDR2 Patriot 4gb 800mhz

Now the problem(s):

Firstly, I recently acquired a Corsair H80 cooler for my CPU and decided to take a stab at overclocking. I had just recently formatted jumped into a game of Tribes Ascend. The result was a framerate of around 25-40fps and light stuttering increasing to massive stuttering as the game progressed. I defaulted the BIOS and tried again at stock settings and the results were the same.

Secondly, when I was trying to format the Windows 7 installation was moving at the pace of a mummified slug. It took over 20 minutes for some of the conformation windows to pop up. I tried moving, removing, and swapping various components to try and solve the issue but it resulted in nothing. In my previous Windows7 installation, the boot-up time was horrendously long. It took about 15 minutes to get to a full boot. The computer would just sit there and chug.

Please, do not hesitate to ask if you require further information. I would really like to get this resolved!