This SCII, Shogun, Civ V all struggle on AMD processors, I've played team monobattles on an 8350 and a 3570K, and the AMD quite clearly does worse in such instances. In general any game that focuses on single core performance and hundreds of units on the map at once (RTS games) will cry for more single thread performance. A better GPU will not improve your FPS in SCII much at all, rather a heavily clocked CPU will. I also laughed a little when I saw the passmark comparison for CPU's. I dont think Passmark is a valid benchmark to use if you consider what the OP is asking about. Considering he's talking about 660ti's in SLI.