OK, so here is a quick analysis of the data at http://www.hexus.net/content/item.php?item=16300 And now for a quick analysis: look at the Excel table below. The numbers in black are data from Hexus. The numbers in red are my calculations. Clock standardised FPS takes the FPS and scales it as though all clocks were at 4850 speeds, ie 625Mhz. It shows (approx) what the FPS would be if we OC the 4830 and underclock the 4870. FPS per shader takes this standardised FPS and divides by the number of shaders on the GPU. LOOK! The 4830 is the most efficient card (100%), with the crossfire (2x) 4830 (92%) coming next and the 4850/4870 somewhere behind (78%/81%). In COD4, the 4830 is about 25% more effective per clock per shader than the 4850/4870! Why is the 4870 better than 4850 if they have the same shaders and we standardised the clocks? Because of the faster memory. BUT even with faster memory, is still underperforms the 4830 clock for clock, shader for shader. The 4830 is 25% faster. So what gives? Easy, there are only 640 shaders on the 4830 but 40 texture units and 16 ROPs just like 4850/70. THEREFORE, the 4830 is a more optimal combination of shaders, texture units and ROPs. Since texture units are 40 compared to 16 on the previous gen cards 3xxx, but the ROPs remain at 16, then I conclude that the ROPs is the primary bottleneck on the card, followed by the texture units. Why because adding more shaders on the 4850/70 doesnt increase the relative performance. We need more ROPs and more texture units in R800! Not more shaders! (Relatively speaking).