considering I play on very high graphics with my 17 inch toshiba qosmio laptop and no lag, the fact that an overpriced alienware can is not surprising at all.
TOR really isnt all that demanding.... with a ton of toons, maybe, but your specs are WAY over what they need to be
560ti 1.5 gb video
i5 2.5 (boost to 3.1 or something)
6 gb of RAM
runs the game solid, ive never felt a glitch