I would assume you have both of these systems already... So... why not try to play your games as is on the system you plan to take w/ you?
Your old computer is still decent and should play the games you listed just fine - as long as you turn AA down a bit and are not playing on 1440p+
Okay so I guess you are telling me I should run both machines in SLI, since the 460 SLI running at 1920x1080 is enough to play the games I stated, I will keep the other in 670 SLI then, thanks.
So I assume 6G ram is enough as well?