AMD's RV790 and RV740 samples in circulation
 

Accordingly, the current RV790 samples work with 750 MHz on the chip and are equipped with 1024 MiB big, 900 MHz fast Qimonda GDDR5 memory, which is bound to a 256 Bit wide interface as unsual.
AMD's RV740 chips also do some testing rounds eagerly. Here samples with 700 MHz core frequency are going around – there are still experiments with the memory. So AMD bets, as suggested in face of the 128 Bit wide interface, on GDDR5 memory, too. This is between 512 and 1024 MiB wide and runs with 800 to 900 MHz.

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