The U2711 is a wide gamut monitor, right? That means you need a video card that is capable of doing 10 bit color if you want to get the most out of it. You'll have to get a professional card (like the ones made for CAD), either an Nvidia quadro or ATI Firepro. I've also read that the consumer Nvidia cards will do it, but I don't have any personal experience with them and I've only seen it a couple places. I know the comercial ATI cards won't do 10 bit color. It's stupid because they are more than capable, they're just crippled so that they can't.
As far as i know the IPS panel in that monitor is only 8-bit.
Edit: it is 8-bit with ARC for an emulated 10-bit, but either way the pro workstation cards are well out of the price range.