I'm currently running an AMD 8150 at 4.15Ghz on an ASUS Sabertooth 990FX mobo with 4 GB of RAM with 2 550Ti's in SLI. I'm pretty sure this is enough to run it on ultra right? Thing is, the game has got some serious occassional stuttering when using both cards, but not when I'm using 1. Any idea how to fix this issue? It's not the RAM is it? Or does the 8-core create some complications? Any help?