Quote Originally Posted by -Boris- View Post
No, a VLIW4 SP is most likely a tad slower than a VLIW5 SP. But a 1536 (384) shader VLIW4 chip will have 20% more real useful SPs than a 1600 (320) VLIW5 chip.

A 320x5=1600 chip will have a lot less useful power than a 384x4=1536 chip.

Even if a Cayman shader is 96% of a Cypress one performance wise, there are still 20-50% more of them depending on which rumor to trust.

Your number of 20% higher performance is based on 20% more shaders.
You also have to look at where the cards are performing relative to one another

If the 6870 is ~5-10% slower than the 5870, how can the 6970 be only 20% faster than the 5870 if there's a 6950 to slot there too. Assuming the 6950 and 6970 have a 20% gap in performance (akin to 5850 and 5870), you'd certainly have to expect the 6950 and 6870 to have a sizeable gap as well. From there one ought to extrapolate where 6950 and 6970's are going to perform