- Forum: Current Mac Hardware
In a 2GHz G5 the FSB runs at 500MHz - there's one channel for read and one for write only for each cpu. It is double pumped, so it's called 1GHz. As with all DDR (or QDR as in the P4) buses doubling the speed declaration is a marketing trick. DDR does not virtually double the speed of a bus - it would be better to say it virtually doubles the width of a bus. Read the article about SDR and DDR at ars technica "understanding bandwidth and latency".