- CPU and graphics card are not upgradeable (99% of cases).
- laptop will get hot and maybe noisy when running games.
- mobile CPU and graphics have lower performance compared to equivalent desktop model.
I do have a laptop with i7 and AMD 6990M. When running Diablo 3, gets hot and fan is really loud.
I just purchased an Alienware M14x r2 with an i7 3610qm, 500gb HD, 6GB ram, and a Nvidia gt 650 1gb. It has a 14 inch screen with a 1600X900 resolution. I got it for $1300 actually so it'd fit your budget well. Now i will admit that alienwares are a tad over priced but imo they're worth it. The build quality is the best of any laptop I've owned, they look freaking cool, and the battery life is amazing on them. For me it a great college laptop that can game. Only thing I dont like is the thing gets loud playing bf3, although I've never seen temps above 75c which isnt too bad (that is during a BF3 match). Its plays BF3 quite well along with any other game I've tried on it.