What video card do I need to upgrade my dell Dimension 2400?

I need to upgrade my dell Dimension 2400 I've put in 500GBs of hard drive plus a 250GB hard drive so can anyone tell me please what video card i need

thanks|||Dimension 2400 power supply is 200 Watts or 250 Watts.



Dell Dimension 2400 Replacement 480W Power Supply B110

http://www.cputopia.com/hp-480w-dell-dim…



JATON VIDEO-558PCI-Quad GeForce 8400 GS 512MB 64-bit DDR2 PCI Video Card

http://www.newegg.com/Product/Product.as…