Check the manual of your mainboard to see what type of ram it supports. You can get the fastest high grade RAM and pay through the nose for it, but I doubt you'll see much much difference in PS. You're likely to see more of an advantage there in games (i.e. slightly more fps). But it's really just marginal differences.

What does help is getting a set of matching RAM sticks in terms of stability and speed. Lots of brands offer 'matching stick' packages. In other words, replace the 1GB you have with all new 2GB memory. Seems like a waste, but at least it'll keep your memory sticks from fighting eachother :P and it's not like memory is all that expensive anymore (say $90 for 2GB).

What is a friend? A single soul dwelling in two bodies. - Aristotle
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