And the correct drivers are installed? I do not find the same information on that Video Graphics card...
From the ATI site, "AGP 2.0 Compliant BUS - AGP 2X (3.3V), AGP 4X (1.5V), or AGP2X/4X based systems, PCI 2.2 compliant - PCI-33 and PCI-66, or Universal PCI based systems"
and
"AGP and PCI Bus"
The trick is the "... Universal PCI based systems..." which the Dell 3000 is not.
So drivers and install are going to be critical, as well as the Dell install.
I would try it in the other two PCI slots in your 3000...
Did you buy it new or refurbished? Because the common use has been for older MacIntosh computers that cannot exceed 4X.
What do you find in your Device Manager, once it is installed in the slot? Do you have red or yellow or black flags there?
I do know that the Dell basic models from 2200, 2300, 2350, 2400, and 3000 have a history of being very particular about which PCI video graphics card are installed... and a great number of cards will not work. Ever. Due to the limitations on those very basic motherboards.
Good luck to you. Please get a final response to this site once you finger it out.