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At first glance, they all look the same (in terms of type of memory). You can just pay more for a more reputable make if you so desire. I'd probably go for the Corsair ValueSelect 2GB memory. Simply because I've heard of the make, its original price is $69.99, is on at $49.99 and has a rebate giving back $15.00. Seems like its the best deal - decent make and the cheapest.
 
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