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As far as buying RAM goes www.macsales.com is pretty good. You can even get them to buy back your current sticks. Not bad at all.

Edit: Eidorian snuck in a moment before me 🙂
 
With your current uses, does your computer normally use up the 2 GBs you have? Are there a lot of page-outs?

If you don't currently tax your 2 gigs, 4 gigs shouldn't make a difference.
 
Well, I'll be playing COD2, installing Windows XP soon, (just purchased on eBay for an AMAZING price) and playing games such as BF2 and COD4. So I don't know if it will make a difference but I saw a bunch of these videos of this guy who had a the middle model of MBP's and had 4GB RAM and was playing a bunch of games like COD4 and they looked amazing. That link you sent me had 4 GB RAM for only $99.99!!!! That's incredible!! But I don't know if I'll need it... But I have to admit that is an amazing deal.
 
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