Anything by Dell ensures it's gonna be packed with several Dell labelled programs 'powered by dell' which will slow the computer down immensely, several of their own size specs for hardware so they an try to make you only buy from them, and of course a bomb inside that will explode if you start shopping for a new pc from anywhere but Dell on the internet (don't test this theory, the things I've seen...*shiver*). Doesn't look like it has the best ventilation it could either, which is stupidity when you get to the point of 4 gpx cards, that much ram, and 2 HDs. Components'll wear fast too (it's a Dell, they build their pcs expecting you to upgrade through them in the next few years).
Four of those Geforce things will run any game on the highest settings, with beautiful graphics
Some games only run on ati cards, for example Thief 2: The Metal Age (a great game at that)
Better off building your own, or choosing a different company.