I have tried a small handful of ATI/AMD cards over the years and have never had good results. Performance in Windows was always mediocre and I had massive stability or features not working on Linux. I will admit my last attempt was several years ago (less than 4 though). I'm not talking about embedded or mobile chipsets either, but dedicated AGP or PCIe.
(before you go all AMD fanboy on me (I'm hoping you wouldn't but just in case), I should mention I've been using AMD processors since I abandoned my old Pentium 3 back in the day, and my first few processors were cyrix)