Quote Originally Posted by imperium View Post
You said the controllers maximum throughput is 666MB/s, but the burst rate is around 3000MB/s. Do controllers have a burst rate to?

Could someone explain?
If the data requested is in the controller cache, then you'll get burst speeds reading it across the bus into main memory. Otherwise, the speed of the onboard processor will determine the limit on how much data can be read sequentially off-disk. If it's having to do parity calculations, there is a limit on how many can be done per second. Bigger cards use beefier (or dual) processors, clocked higher, not just more cache.