
Originally Posted by
blade4638
ddr400 = pc3200 (not pc400. there is no such thing)
* the number after "ddr" is the memory speed (e.g. 266, 333, 400, etc.). this is the standard name.
* the number after "pc" gives the rounded-off (theoretical) peak data transfer rate. this is the module name
e.g. for ddr333
- mem clock is only 166MHz, but since 2 transfers are made during each clock, data transfer rate is 2 x 166 = 333 million data transfers per second
333M transfers/sec x 64bits (bits of data transferred at a time) x 1Byte/8bits = 2656MB/sec = 2700MB/s (rounded-off to nearest hundred so its easily remembered)
this is how we get pc2700, which is the same as ddr333.
try this on ddr266 (mem clock is 133MHz), to get pc2100 c",)