Ok guys I have a strict $300 dollar budget. What is the all-around best graphics card taking into consideration DX11, ATI's lack of stable drivers, noise etc. I have a Dell XPS 430 with an Intel core 2 quad Q8200 @ 2.33 GHz, 6GB Crucial DDR3 @ 1066 MHz, 425-Watt PSU, ATI radeon HD 3450, generic dell motherboard @ 1333MHz with an X48 chipset. Thanks to all for the help.
You will need to upgrade your PSU to run a good card. Not sure why people are always ragging on ATI drivers, they a very good these days. Aside from the PSU budget, the best GPU for that price range is the 5850 but it will cost you about 320, if thats over your budget, then consider a GTX275 or 4890 instead as they will offer the next best performance, a 5770 would produce little heat, provide DX11 capabilities but it is less powerful, it performs about the same as a 4870.