Hmmm, all those links work for me so I dunno. In any case, if you are having troubles then you can get both the BIOS's directly from Dell support and the Omega drivers at www.omegacorner.com
The Omega drivers are (from site): "ones that have more options and features than the original sets. The drivers contain optimizations, extra features (like OC capabilities), more resolutions and internal tweaks that can give them the edge in a gaming enviroment over the normal drivers, which are often tailored for synthetic benchmarks."
They are miles better than the Dell releases and are even optimised over the ATI release. They will offer you the best performance in games and some overclocking ability if you wish to do that. They also come packaged with Radlinker, a program that you can use to have each individual game/ program available through a link, that automatically changes the video settings to the custom ones you specify. Very cool.
They are 3rd party, but they are endorsed by ATI as one of the best enthusiests and are very good quality I can assure you.
For installation you must uninstall your previous drivers, including the control panel for them, before installing the Omega's.