So I need to get a new laptop on account of this one literally falling apart in my hands. I'm torn between two models I saw. One is slightly superior in every aspect and $120 cheaper to boot. The extra cost of the other one, I am told, is due to a smaller size (improved portability), which translates to a smaller screen, which is actually a negative in my book, since I use the computer mainly for reading, writing, watching videos and internet stuff all at once, so the bigger the screen, the more room for more windows. So everything works out.

The only problem is that the other main thing I use the computer for is playing video games. Especially the newer Blizzard ones. I have barely played Diablo III since the week it came out, due to the hardware issues with my computer, so compatibility with that and similarly advanced games is a prime motivator for getting the new one.

The major difference between the two computers I was looking at, is the otherwise inferior one has a superior graphics card.
The better computer has a default graphics card that comes with an HP Intel whatever computer, while the other one has an AMD Raedon HD 649. I'm told that this one has memory dedicated to the graphics and they'll work a lot better with this computer, while the other one might have graphics that are choppy. They otherwise have the same processor.

So my question is, does anyone know how much of a difference the better graphic card would make, as far as playability goes? Aesthetics are pretty much lost on me, as I have disliked the look of every Blizzard game released in the 21st century, and on other games that were at the outer edge of my system's capabilities, I have had no problems turning the graphics options down as low as they go in order to run the game. Will the graphics card really improve play quality enough to justify spending extra money for a smaller screen and 25% reduced battery life?