Howdy people.

I'm thinking about updating my slightly dated graphics card. It's a GeForce2 MX with 32MB of RAM. I'm running it on a Dell Dimension 8100 (or maybe 8200, can't remeber exactly - it's at uni and I'm at home).

Basic specs are:

Pentium 4 1.8GHz
512MB RAM
Windows XP SP2

Now, the AGP slot runs on the 4x protocol, so what I'm asking is...

What's the best AGP 4x graphics card on the market?
What's the best value for money 4x graphics card on the market?
...and if you're extra knowledgable about these matters...
If you were me, what graphics card would you get?
Would I be better off getting more RAM?

And waiting for a new PC is pretty much out of the question.

Thanks.