Which Vid Card for Dell 1905fp

I got a great deal at Dell's small business on a 19" Ultra 1905 last night and will be buying at Dell 8400 at the Outlet and wondered which video card will be better for this monitor the 128MB PCI Expressx16 ATI Radeon X300 SE or the 256MB PCI ExpressTM x16 Nvidia GeForce 6800? I plan on connecting via DVI, is the 256 worth the upgrade with this monitor.. Also one Outlet question, if the SB Live or Audiogy is not listed as being on the computer does this mean it has an onboard integrated sound card?? Sound quality isn't a big issue for I plan on using the sound bar from dell that attaches to the monitor so great sound isn't a real possibility with those speakers.. just kind of worried since I heard stories of integrated sound cards going south and not being able to disable them to install a new slot card.. any truth to this??