+1 for the 4670 AGP.
It is the best of the limited bunch.
IMO it will be totaly wasted on his rig even after the upgrades.
Unless he is getting the RAM and CPU for free, tell him to save his cash for a real upgrade.
For under $200 he can upgrade his Motherboard
for a much more capiable system.
As you are probably going to spend around $100 on the AGP GPU alone....