His motherboard is probably this one:http://www.amazon.com/Dell-Motherboard-Inspiron-Systems-Compatible/dp/B003CO0WQS
It says in the specs that he has a pci-e 2.0 x16 slot.
So basically, if that is your motherboard, then yes, you can upgrade your video card.
EDIT: You have a pci-e 1.0 x16 slot. Still, there is no problem since pci-e x16 2.0 cards are compatible with pci-e 1.0 x16 slots.