goes up in factors of 8 so
64
128
256
512
1024
[ anyone seen a stick of RAM bigger than 1024? ]
you could get a 512 and then add you would have 640MBs, which is loads.
why is you think you need more RAM? what sort of stuff you running on your comp? im not saying anything is wrong, im just gathering info
to use it all you gotta do is open your case and whack it in there ( not literally ). anyone can do it. you will have more than one slot for RAM so you can add at least 1 more stick.
i have 4 slots with capacity of 4GB RAM [ MUHAHAHA ].