how important is it to have equal RAM? ie two 256s or two 512s?

i currently have two 128 and am considering buying a single 256 or even a 512

also, i'm running PC100 cards, would my motherboard work with PC133s?

on some sites it says 'high density' do i need to worry about that? is it compatible with my PC?

thanks, James

A good place to get all of your memory questions answered is at Crucial.

www.crucial.com

Jim, Low Density RAM is what is preferable for Older hardware such as yours. I should know. I have dealt with SDRAM alot. High density has fewer chips and is picky on what it is compatible with.

eBay Guides - PC133 MEMORY COMPATIBILITY ISSUES - the truth

eBay Guides - MythBUSTED Density Facts