There is no real need to do that buddy. Only reason i could see is not being satisfied with your GMA950. Even if thats the reason it's a nice card for a laptop, supported in OS-X, QE/CI enabled. Better card only if you intend to play really high demanding games. I used to play Quake and Doom 3 on my C2D MacBook with the same graphics and it run very well. And if processor is Intel DualCore or Core2Duo then you'll be more than satisfied with your laptop.

You can invest a little and upgrade it with 1 more gig of ram. You can do it yourself and it'll be pretty cheap. With 2 GB of ram it will work like a charm. You can also replace your hdd with a bigger one but they're around $70-$80, so you can do it and you don't have to, or at least if there is a real need.

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