I hear this over and over, so can somebody tell me why Apple uses DDR? Do they really get a benefit or is it just for show? Is it needed for other things on the motherboard, or does the CPU benefit, too?
I reckon just for show, they don't want to look *that* far behind the times. I guess that they'll fiddled things so that the actual DDR capabilities are ignored and the RAM is actually running in SDR mode, just that the technology is slightly newer and better, hence the very minimal difference in speed.
Of course DDR is going to make a significant difference (if the CPU, RAM and motherboard support it) - at the moment, you have a situation where the CPU is clocked nearly ten times over the RAM clock. This means that every time the CPU makes a request to query values in RAM, it has to wait whatever factor of cycles the CPU is clocked over the RAM, cycles that would have been better spent doing stuff. Every architecture, when doing 'real work' makes significant amounts of calls to system RAM, unless you're going to come up with a CPU that has something like 32MB L1 cache :-)
People, do you realise that UDMA and DDR were advancements made on the same concept? Both advancements were made when designers found they could get away with twice the amount of signals in a cycle, on the rising and falling edge, rather than (I think, could be the other way round) just the rising edge of the signal. Being able to send twice the amount of data than before on virtually any bus is going to have a significant benefit (except of course all you ever use your system for is Solitaire!).
