My two 670's are waiting to get the scooch down the bench to my old computer (pending reviews and benchmarks for the 9000 series). If the 7990 is anything to go by, the only game that I will not be able to play at max settings will be Batman. Pretty exciting stuff.
I hope you aren't wedded to the "9000 series" name.
44 CUs is almost perfect gpu utilization when you figure the actual gaming performance difference (not counting compute-intensive perks) between 7970 and 7950 (or gk104 for all intents and purposes considering 256 sfus really make it 1792 ops anyway) per clock when accounting for their bandwidth requirements and excess...That is to say somewhere around 1877sp per 32 rops is exactly what they would want.
900mhz is perfect for a process that was made for a nominal power/performance/yield voltage of .85-9v and has attributes of approx 1ghz/1v.
fwiw, 900mhz and 2816sp would require 5940mhz on a 384-bit bus. 2560 at 1ghz would be 6ghz.
This sounds very un-ati-like.
I was very much expecting 40-42 (36 pro) units and 7ghz (6ghz pro) ram because of the clockspeeds 28nm is capable (to keep die size down) and available bw in the said power envelopes this gen, but this would be better for power consumption. Clockspeeds would be lower, but it should yield well at those clocks and consume less power considering the trade-off of around 10% clockspeed for 10% efficiency (that would be fairly linear with sufficient bw) and around 6mm-7mm2 per CU.
They can cal it 3CP0 as long as it works well.
There is no "perfect" here. Power consumption is governed mostly by defect management in this day and age, combined with leakage characteristics. Memory bandwidth efficiency is more important than sheer bandwidth.