Hardware entusiasts have proposed an easy way to make your Radeon HD6950 graphics card perform like a Radeon HD6970 through a software Unlocking process, which could save you some $70.
According to an article at the TechPowerUp web site,
AMD's new Radeon HD 6950 can be transformed to a Radeon HD 6970, unlocking 128 unified shaders in the process.
Both the Radeon HD 6970 and Radeon HD 6950
are based on AMD's new Cayman core which is their first graphics processor to use a VLIW4 shader configuration. AMD's two Cayman variants, called Cayman Pro and Cayman XT, are based on the exact same GPU silicon. The web site reports that the two SKUs are sharing the same silicon so a software modification is enough to unlock the "locked" features of the HD 6950, essentially transforming it to a more powerful HD 6970.
Unlocking the additional shaders of an HD 6950 is done by flashing the card with a HD 6970 BIOS. Any of these BIOSes will work on any reference design HD 6950 card, according to the modders.
According to the unlockers, Radeon HD 6950 cards from Club3D, XFX, Sapphire, PowerCooler, ASUS, HIS, and AMD, all were able to be upgraded via the firmware unlock.
"Enabling the shaders without any clock increases improves performance. Once the clock speeds are adjusted to match the HD 6970, the card effectively performs just as well as a full blown Radeon HD 6970," the web site claims.
A Radeon HD 6950 retails online for around $300, while the cheapest Radeon HD 6970s are selling for $370. A Radeon HD 6970 could offer a performance matching the GTX 570 ($350) in some games and even nearing the GTX 580 ($510+) in a specific benchmarks.