RV740 is not a high-end graphics card. The chip will be the successor to the RV730 (Radeon HD 4650/4670), AMD can redefine the budget to middle class product line-up. See, performance of the strongest RV740 based product will move upwards in-between HD 4830 and HD 4850 performance.
RV740 is based off a 40nm production node and is equipped with 128-bit memory. Now before your go "aaahw, we lost half the framebuffer bandwidth due to 128-bit memory", here's the thing. The RV740 is equipped with GDDR5 memory.
Now if you cut down the memory bus in half to 128-bit you lose half the bandwidth, ATI compensates for that by doubling it up again with GDDR5 memory. It's a bit of a tradeoff here and there. See, 128-bit memory is fairly cheap to use and does return a heap of framebuffer bandwidth thanks to the higher frequency memory. Also I can imagine a simpler design in the PCB such as using less wires and thus a cheaper design. On the flip side, slower memory latency timings. But granted, this choice makes a lot of sense, as the results will show.
