Actually, if it's in your budget, stay away from ATI/AMD as well. Although they aren't terrible for you windows (And hackintosh) users, it's horribly limiting for us Linux users. And nowadays, for desktops, there are affordable Nvidia cards out there on the market for less than $100 USD. But again, you can disregard me all you Windows and misc. users who aren't Linux. ;)

The HD 4000's series ATI card I own, made by MSI, is rather crappy. It gets good framerates for most games, but has horrible visual artifacts like image bleeding. I plan on getting Nvidia myself soon, when it's back in my budget again.