I do rendering in 3D Studio Max R5, and it helps os much having 2GB RAM. Just normal everyday stuff though, 1GB is fine. And I'm completely new to MMORPGs (yeah Guild Wars), but I was amazed by the performance on there, so it very well might help in there as well. On the other hand, I'm forced to use PC2100 RAM, which sucks, because I know how much timing affects performance now, so get the best speed RAM you can.
Tas.