First of all , I be wary about upgrade from my previous card -lrb- the Radeon HD 5770 hawk -rrb- since it run damn near everything -lrb- and still do , mostly -rrb- . for I to purchase a new card , it would have have to be a massive improvement and within a reasonable price range . I consider the hd 6850 , which be supposedly ~ 50 % better performance-wise , but go with the hd 6950 which be purportedly 100 % better than the 5770 . it be : - -rrb- this be a huge card . it just fit in my -lrb- Cooler Master mystique -rrb- tower to within 1 cm . it require a `` 500 watt or greater power supply , with two 75w 6-pin PCI Express  power connector '' . just keep those spec in mind . that say , my hardware fulfil the requirement so I go ahead with the install . it be advisable to first remove or uninstall any automatic overclocking on you current card -lrb- mine be the hd 5770 -rrb- and completely uninstall its driver . I do just that , fit in my hd 6950 , reboot and install the driver that come with the CD . worked fine until I decide to upgrade the driver . I get a immediate bsod -lrb- blue screen of death -rrb- which come back every reboot after a few minute -lrb- fault `` atikmpag . dll '' -rrb- . the only way to solve it be to install completely and reinstall the download driver . since then it work fine . I suggest therefore that you do not install from disc and then upgrade you driver . just download the latest driver from ATI and use that . I choose the Sapphire model in particular for the two fan and large copper pipe that comprise the heat-sink . the extra cooling on the Sapphire be a boon to those who wish to flash\/overclock this puppy . the hd 6950 can be `` flash '' with the bio of the hd 6970 make its value even better ! of course this be risky and will void you warranty and possibly brick you card if you do not know what you be do ... another reason I choose this particular model be it seem to be the same as the dirt3 edition ! -lrb- minus the game of course ! -rrb- all in all great performance , 4 star for the driver issue I have but flawless performance since then .