With the current economic environment, if you don't offer real value for price (who in the world would buy a card which only has a better idle consumption for, let's say, 50$ or € more?) you will experience serious problems in selling your products...
I guess that depends. For example on whether or not or for how long you will/can allow those two products to coexist in the market. If you can limit this time to a pretty short amount, then it would really be cool to improve upon the margins a bit.
BTW, please note, that I said, that the addition of a better idle mode would make the product more compelling than
just raising clocks, so i didn't exclude that from happening.
Then, again, with R420 there were yield issues, so the transition to R480 was an advantage for the company, but now, what kind of advantage will AMD get from such a chip (given that it doesn't seem that RV770 has a problem with yields...)?
I am not familiar with the delicacies of all of TMSCs process nodes at 55nm listed
here, but I'd assume "Vt" standing for voltage, an the GC-option offering a different choice including something called "ultra high"…
Develop even a chip revision could be very expensive, so why take the risk just to improve consumption or only to slightly rise clocks? If I had to finance something like that, I would invest to further move the market (i.e. targeting higher positioned VGAs...).
Again, I am not sure how costly it would be to just port a given design from 55GP to 55GC. Maybe, if it's not too expensive, AMD feels that it is the right thing to do to bridge the time to coming 40nm-GPUs.
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I just want to make clear again, that I am not thinking predisposedly in any direction right now. I do not consider it a given that AMD may or may not stay with the same chip nor that they necessarily had to add additional SIMDs/RBEs to improve in performance in the rumored percentage range.