I really want to believe it 25-40% faster than the 4870x2. That would absolutely awesome. If its only being compared to R770 or R790 then I'll pass... At this point I'm assuming 1600SP is the case ( makes the most sense ) so I don't see a doubling of shader units, increased throughput and more rops as only managing 25-40% over a 4870...
Hopefully tomorrow something tangible is revealed...
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