How do I buy RAM, The good ones.

I don't know shit about Ram, is there a site that explains the difference between them and features some of them have, like the dual channel and stuff.  SAVE ME!!!!!!!!!!

>>1
You probably have RDRAM. YOu just need to replace it with more RDRAM, speed doesn't matter, though higher is better. Also, you need at least 2GB of it (total).