I have an early 2008 Mac Pro and at the moment I have ATI Radeon HD 2600 XT 256 MB. It works but it isn't very great at all. Gaming is a disaster and I can barely edit HD videos on FCP. Does anybody have any ideas on what graphics cards are good, new and will work in a computer this old? I just don't want to buy some random card and have it not run on this computer.