dumb question dual channel

if you have 2 sticks of ram 2gb each 4 gb total of ram, but you run them in dual channel .do you really only now have 2 gb of total ram because they are accessed in parrellel (by theory) even though this wont show anywhere on your stats?
and if not can anyone actually explain why this isnt true?

Never thought about it. Good question.

Think of it like Raid 0, you get 2x the performance and 2x the size (in theory).

you still have 4 gb total ram. in a dual channel capable mobo you have 128 wires running to the memory controller vs only 64 in single channel mode. what that does is double the maximum theoretical transfer rate. so it doesn't reduce the overall amount of ram, it just doubles the speed (in theory) at which it can transfer the data for each clock cycle between the memory and the memory controller.

Dual channel is good to have, but in practice only nets less than a 10% gain in performance. That is why everyone is prefacing their comments with "in theory."

Random Benchmark link: http://www.devhardware.com/c/a/Memory/Dual-Channel/3/