[BBLISA] RAM speed difference?

[Daniel Hagerty]

Scott Ehrlich <scott at MIT.EDU> writes:

> What is the speed difference between 1 x 4GB vs 2 x 2GB modules?

    On most modern machines, that's the difference between running
dual channel or not (memory has to be in pairs for dual channel), a
theoretical doubling in speed for memory transfers.  Reality is less
so, since dual channel is an interleave across the banks.  Your access
pattern affects how close to double you get.

    There are very few reasons to pick a single channel config over a
dual.  Real world benchmarks tend to show the difference being minor,
but if it's 6 of 1 vs a half dozen of the other, go dual channel.