Should it show 200mhz or 400mhz?

[spartan92]

Probably a dumb question, but I haven't built a machine with dual channel memory before:

My motherboard supports and I purchased DDR400, but in the BIOS, it shows as operating at 200 mhz. Is this because it's 200 x2 for dual channel to make it 400 mhz? Or is my RAM only operating at half the speed it should?

 

[pickxx]

It is at the correct speed....

if you care why, google...lol

 

[mpjesse]

DDR400 RAM actually operates at a 200mhz clock speed. DDR means "double date rate." In a nut shell, the bandwidth is 2x what it would be w/ SDRAM at the same clock speed. So it's theoretically refered to as 400mhz since the bandwidth would be nearly the same w/ 400mhz SDRAM.

Make sense?

Things get even more confusing with DDR2 RAM.

-mpjesse

 

[spartan92]

Got it. Thanks for the explanation mpjesse