Hackers have discovered how to tweak the BIOS into thinking a Radeon 6950 is actually its older, more expensive brother the 6970 which cost about $70 more and performs better.
Both products are built on the exact same 40nm GPU silicon and are equipped with 2GB of GDDR5 memory as well as 256-bit bus.
Hacking the 6950 will give you some performance enhancements but, not without the risk of messing up your BIOS so please make a backup first.