Not too late, right on time. AMD has experience when it comes to gluing two cards together on one board and if they're not releasing any new GPUs, this could be an inexpensive and easy way for them to remain in the market. Two 7970s give a decent bit more performance than a Titan (and a whole heck of a lot more compute performance) and they cost a bit less. Quite a bit less. 2.5x less.
Extending the lifetime of the HD 7000 series should help drive AMD's manufacturing cost down and allow them to maintain a profit while lowering prices. The 7970 is a strong card and I wouldn't be surprised if AMD just rode it out, lowering the price as nVidia gains the lead, until they're mostly done fulfilling their contracts with Sony and Nintendo. Who knows. Maybe we'll even see a tri-GPU HD 7995 if AMD is lazy enough.
TPU's review shows the 7970 GHz edition to be about 80% performance of the Titan. For the price of, to make this easy, two Titan cards (200% the performance of one Titan), one could buy 5 7970s (400% the performance of one Titan). This is, of course, ignoring power and space requirements, but that's what a 7990 would address. 60% more performance for less money.
The only bad thing I see here is nVidia will have the high-end market all to themselves which, I suspect, will cause them to go mad with power and start charging an arm and a leg for their products. I expect AMD to happily play the waiting game here. It doesn't sound like nVidia has a new architecture ready anyways. If they did, they wouldn't dare make the Titan obsolete by releasing it now.
I'm not saying the Titan isn't an impressive card, and even though I personally prefer AMD, I still tip my hat to nVidia. It's just not as impressive as the price would imply and that leaves a lot of room for AMD to, just as this article says, slide in a very cost effective and sensible HD 7990.
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