Evga 680i q6600 vs GA-MA785GM-US2H AM3 Athlon X3 435 Rana

I built a new computer as a graduation present for myself back in May. My problem is that I'm trying to build my fiance a computer able to handle Star War The Old Republic without buying a whole new system. I need this system to play the game smooth since she has vertigo. She will be using a 22 Inch monitor with a 1680x1050 Screen Resolution.
I know the game isn't out yet but I would like to start planning now since Black Friday is coming soon.

The system she now has is this:

Case: Antec 600 Case
Motherboard: GA-MA785GM-US2H motherboard
Processor: AMD Athlon II X3 435 Rana 2.9GH
Ram: 4 GB Patriot Viper 2 DDR 800 CAS 444
Video Card: ASUS CuCore Series EAH4850 1gig 256-bit DDR3
CPU Cooler: Hyper 212+
PSU: 620 Antec Earthwatts P/S

My Old system

Case: Antec p182
Motherboard: Evga 680i
Processor: Intel 775 Q6600 2.4 Ghz Quad
Ram: 6GB CORSAIR XMS2 TWIN2X4096-6400C5
Video Card:
CPU Cooler: Stock
PSU: 650 Seasonic P/s

I know one thing for certain. I will need to buy another video card and I was thinking a Geforce 460 1gig would pretty much make the CPU the bottleneck. What would give me the best performance scenario? Two things that came to mind was overclock the Athlon system, put in the Geforce card and call it a day. But I had no idea I could get the Q6600 to 3.0 Ghz, and maybe even higher. I was thinking if I got an ARCTIC COOLING Freezer 7 Pro Rev.2 I could over clock the Q6600 to 3.0 Ghz or more. Which would be the better route. Now if I'm going to install a HSF with the intel system I found that the Arctic Freezer actually clears the north bridge on the 680i motherboard where the hyper 212+ does not.

I know either way I go I will be over clocking. I found some good videos for the q6600 but the Athlon 2 is a different story and it sounds much more involved so if anyone could shed some light I would appreciate it.

Thanks for your guys time and input.