I never thought I'd hear myself say this, but it may be worth going to PC World and having a look at their own graphics cards. They are NVidia GeForce cards, but without the fancy packaging. You get one in a brown card board box without any fancy marketing blurb. The NVidia drivers are included on CD Rom.
Can't remember exactly which cards they do, but they're extremely cheap. (AGP & PCI Available)
F - Wyg.