Memoreeeeee

Hey guys here at technology, i'm a psychic, but I am not computer literate. I have only 512mb Ram on this comp, and I have a Asus P5GD1-VM motherboard, and i've asked people about what kind of ram I could get, yet noone gives me the same answer, so I turn to you, the internet.

tl;dr
I have an Asus P5GD1-vm. I do not know what kind of ram I can get. Could you tell me what would work in this mobo? Thanks.

If you help me I predict a happy future for you.

Any specific brand or type you recommend? Either just gimme a name or a link to newegg or something, I have the idea now, I just want to see people's opinions.