Quote:
You know, I could handle 512mb.

But you don't have to.

http://support.dell.com/support/edocs/systems/dim2400/en/sm_en/specs.htm

Although they don't offer the configuration (you can't even customize this one on the website), the motherboard is capable of handling a pair of 512MB DDR stick, for a total of 1GB.

But as was discussed... without an AGP slot, do you really want to bother?