Not much you can do... IF you are lucky... Open it up and look for a video card slot. IF you are very lucky, it has one. IF it does, you can put a cheap card in it. Unfortunately, the Dim 3000 suck. They were from a bad time @ Dell.
There are 2 basic type of video cards, PCIE and AGP. IF that has a slot, I think it will be AGP, the slot is usually brown. The expansion slots for Modems and such are white.
(hopefully not) IF your system is like the one I am currently working on, it does NOT have a video card slot.