I think the difference is in the clocking - 9 at 1600 would be 4.5 at 800. So, yes, the memory is being clocked at 1600 but only accessed every 9,9,9,9,24 or so. So yes, marketing ploy back in 2007 - runs no better than a fast 800 clocked at 4 or 5. But "showing 800 and clocking of 9,etc"...