... so this will have old 7950 performance then?
http://img.techpowerup.org/121108/Capture1024.jpg
I think the purpose is clearly to have a product that performs as well or slightly better stock/overclocked at 1080p than 660ti in the 660 price bracket. I also think (as I've said before) this is the place 8850 will sit. The dead obvious spec they need to hit for efficiency/price is 1536sp, 925/5000 and 256-bit, but I believe 660ti was given >150w because they knew amd was going to beat them (with 7870 over 150w and slightly less efficient...8850 under it and more efficient) hence 660ti was carved out to slightly exceed that performance level. A make-shift 7870, if you will, based on a more efficient spec because of the greater resources of gk104, perhaps also influenced by hiking the tdp allowances and placement of 670/680 early on. Point is, this will probably be some take on that carved out of Tahiti and ~185w (just like 660ti)...and we really don't need it. Tahiti was not built for where 1536sp fits. If it's a high-speed product, it needs 6gbps and 256-bit. If it is a power-efficient product, it needs 5gbps/256-bit.
Consider the bw matching/separation game more closely. 7870 needs 4500mhz on a 256-bit bus (hence why you see a lot of 1200/5400 overclocks, given the max 170w tdp one would imagine it was engineered with that realistic overclock in mind). Original 7950 needs 5040mhz on a 256-bit bus at stock...a bad overlap...but the boost version that replaced it (stock 'up to 925mhz boost'...which essentially equates to a 7870 at 1295mhz) would need over 5800mhz at 256-bit. Note the hard locks at 5800mhz for the 7800 series and how 1295mhz/5800 is not exactly common for the process or 5gbps-rated ram, so 7950 boost actually does what the original does not...create market separation within their own stack. This is how products are made these days...A convoluted mathematical nightmare...but even slight mismatching of resources within a price bracket is the difference between an appealing and unappealing all-around product.
I can't help but wonder if this will exist in-part so amd can stop cutting the 7950 price. Since 660ti core efficiency and tdp sits directly between 7870 and 7950, up until now the larger and stronger 7950 has been going almost buck-for-buck with 660ti. Considering gk104 is smaller/less expensive to produce, and both 7870/7950 are probably dangerously close currently to the price they want to launch 8800 series...it would make sense to try to force something into that spot so the next series has at least a little shine on it.
Best amd could do, imho, is give it 384-bit/5gbps and 1.5gb. That should temper the tdp allocation for the ram some-what, and the core could clock to use some of that bw if allowed to scale. In theory, they could stock clock it up to ~1025mhz stock, which would for all intents and purposes be similar-to-faster than 660ti, and would react similar to 2GB buffer without being memory/bw bound.
