Gaming on an AMD 4200+ X2

I'm buying this rig for gaming (BF2, WoW, HL2/CS:S) and I'm reading stuff online saying that BF2 has problems with SLI *and* the X2 line (some saying it won't run on X2 at all).

Should I be worried?

Other notes: I plan on pushing the 4200+ to 2.7Ghz. 2x 512MB GeForce 7900GTX, 2GBs of RAM, 680 Watt PSU, XP MCE, Liquid Cooling CPU Fan.

Use Gentoo.