like what others said, doesn't make sense to upgrade
It has reach that age
1. IDE is slow
2. AGP is slow
3. DDR is slow
still quite amazing your harddisk is still surviving
If you have 500, save a little more
The Dell Online Store: Build Your System <-- even a new pc is <500, though you still need a graphics card and you can reuse your old monitor
I know people will start screaming here when you talk about branded desktops >.<
Don't buy branded or everyone here will scream at you.