Recently we reported about the probable specifications and possible launch dates of RV790 and RV740. As we could learn from AMD-internal sources, first samples of the RV790 are in operation for several days now. The first RV740 examples exist a bit longer.
Before we enter into the various specifications, we want to point out that these are "engineer samples" and so the values of the final cards can respectively still change. But the past teaches us that the final clock frequencies are mostly in range of the samples.
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.
Because the clock rates do just barely differ from the ones of the respective predecessors (RV770 and RV730), we suggest that the performance additions are achieved with more working units. The RV740's last status was 640 stream processors, 32 TMUs and 16 ROPs. We still grope in the dark with the RV790.