DDR1 Graphics Card

PCIe was not made until 2004, and widespread use did not come for a few more years. I don't think any Socket 478 motherboards have PCIe slots.

OP, you need an AGP video card. My old Pentium 4 machine has those specs and had an ATI Radeon 5200, which you might be able to find used online. But since that hardware is over 10 years old, you won't find it new anywhere. And $50 even is a steep price, so go out of your way to find good deals. (Like, $20 or less IMO)
 
Does it look like this ? http://www.asrock.com/mb/Intel/P4i65G/

In which case you have an AGP X8 slot.

The best card it will take is the Radeon 3850 I would guess.

Make sure you get the AGP version of the card, not the PCIe version (aka PCI Express).

It won't run games that require anything above DX 10.1, so be aware.