Over at Chiphell, they managed to get a shot showing the PGA pin arrays of both a Llano APU and a Trinity APU side by side which shows that the coming FM2 socket will be incompatible with the existing FM1 socket based motherboards. The A75 and A55 chipsets will be carried over by AMD to support the new FM2 socket as well as the expected A85X chipset.
Side by side, they may look similar but they are different enough to matter.
The FM1 socket.
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