Quote Originally Posted by Manicdan View Post
if the 6970 is 1536, how many would the 6950 have? and how much performance per SP is needed for it to have a 15-20% gain over 6870 with about 20% lower clocks?
If I do some simple calculations:

Assuming 1 NI SP = 0.95x 1 EG SP,

Barts Pro: 775 MHz x 192 SP (960 SPU) = 148800
Barts XT: 900 MHz x 224 SP (1120 SPU) = 201600
Cayman XT: 880 MHz x .95 x 384 SP (1536 SPU) [rumored] = 321024 = 1.59x Barts XT

Taking around 20% lower clocks from 6870/6970,
Cayman Pro: 725 MHz x .95 x 352 SP (1408 SPU) [speculation] = 242440 = 1.20x Barts XT
(that also gives Cayman XT = 1.32x Cayman Pro)