I appreciate the input, but I want to have a little more assurance that supposition. I've weighed the numbers too, and think it'll work, but I'm not gonna make the purchase until I'm sure. Desktop 512MB cards go a lot further than laptop cards.
Ion is an NVIDIA graphics solution: http://lmgtfy.com/?q=what+is+nvidia+ion
League of Legends is pretty big, but Google should answer your question pretty well. It's SC2-esque, in a way. http://lmgtfy.com/?q=what+is+league+of+legends