There is a rumor that the new GPU from AMD will not be shipping in Q3 of this year but might be pushed back to Q4 or even Q1 of next year. Just as we hear the same rumors about nVidia's GT300.
It could be something to do with the larger more powerful GPUs and the 40nm Process that TSMC is using or it could be a move from TSMC to Globalfoundries that is behind the delay.
Or it could be simply the release of the 4770 and 4890, AMD might want to get them a little more time to run before releasing their replacement. Whatever the reason we know the next card will be a DX11 card and ready for Windows 7 gaming.
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Many has expected that this card will launch either in late Q2 or early Q3, but we are hearing that this card might be pushed to later this year, but that it will instantly come with DirectX 11 support.
This might mean that the original RV870 got cancelled and that the new DirectX 11 card will take over, simply as Nvidia probably goes directly to DirectX 11 in Q4, with its GT300.