so to get back on topic....

http://www.nordichardware.com/news/7...s-dec-15-.html

Radeon HD 6950, Radeon HD 6970
GPU...... Cayman Pro Cayman XT
Node...... 40nm, 40 nm
GPU freq...... 800 MHz, 880 MHz
Memory freq....... 5000 MHz, 5500 MHz
Memory buffer....... 1 GB GDDR5, 2 GB GDDR5
Bandwidth.......... 160 GB/s, 175.9 GB/s