Help overlocking new system

After posting and getting help on my old system and reading articles on best gaming cpu for under 100 and best gpu for under 200 i decided to build my first computer and was excited and nervous. i have succesfully pieced it all together and installed windows and Swtor and everything runs great. the only thing is since i spent 600 on my system i want to make sure i am running everything optimally. so if anyone has any suggestions i would be very happy to impliment them. i am mostly looking at my CPU and GPU as far as what i can improve.

Antec 300 Computer case
Corsair GS600 watt power supply
Corsair Force3 120gb SSD
Windows 7 64bit
8gb (2x4) DDR3 1333 RAM
MSI HD6850 Cyclone
MSI 760GM-p23(FX) motherboard
AMD Athlon II x3 255 CPU
Coolermaster HTX3 CPU cooler

I am not sure what other information is needed and will supply any questions i can. i know this MB bios has an option to unlock a 4th core and has a bunch of overclocking measures that can be taken but both MSI's manual and website dont provide any substantial information on what these changes do or what changes you should make.