Quote Originally Posted by antiacid View Post
Seeing as the 6xxx seem to overclock a bit better than the 5xxx, it's not improbable that factory oc'ed 6990's could be more than just 15-20% faster than the current 5970.

It would be a good time for amd to allow 5xxx cards to be xfire'd with 6xxx cards. If the upgrade in performance is minimal, that would be an enticing way for users to buy the new cards AND gaining a lot more performance
If 6970 is 225W and 6990 has to be 300W, this means an incredible amount of crippling has to be done to two 6970's. And since when you lower the frequency of a GPU its cost to you doesn't magically decrease, this would mean that AMD would be selling a card that, at stock speeds, wouldn't be much faster than a HD5970 (or even a single 6970) yet would be sold at something like $700. Everything is performance/watt when it comes to a TDP limit.

Yeah, I know, AMD will "beg us to overclock" the 6990 too, and by "overclocking" them to stock 6970 speeds we'd get a stupidly powerful graphics card; but the fact is that every review site will base its review on the stock speed, and will add "Overclocking" as merely another page among the 10 something page reviews. It will no doubt make the card look bad in performance and price.

So I don't think that would be very feasible. To me, with Antilles AMD has got two options:

1. Disregard 300W TDP and let the card overwhelmingly break single card performance and power usage records.

2. Build Antilles with 2x6870 instead of 2x6970. 2x6870 is already 12% faster than HD5970. 6870 is already 150W. Doubling it in a card will save one PCB worth of wattage, around 20W, which they can use to increase the clocks slightly to fill it to 300W and around a 15% performance difference from HD5970. The card would cost less than $500, but on the downside it wouldn't have the (possible) tessellation and DX11 tweaks the new Cayman architecture has.