Ok Him, that information you posted is basically incorrect.
You can NOT put two different speeds of RAM in there and expect it to run in Dual Channel. One stick doesn't run dual channel by itself. They have to be two identicle sticks, although if you underclocked the 400 down to 333 then it's possible to perhaps achieve dual channel.
The way DC works is one stick is in channel A, and the other stick is in Channel B, both channels are working at the same time, thus the term Dual Channel.
I don't know where you got 5 DDR slots from man, that board only has 3 slots.
To run in dual channel you'd be a stick in slot 1 and 3, or in 2 and 3 and that would give you dual channel.
Mind you that board only supports 333FSB though so your PC3200 would be underclocked.
To get dual channel you are only using 2 sticks. If you want 1gb dual channel you need 2x512.
Sometimes 2x256 in slots 1 and 2, and then a 512mb stick in the 3rd slot has been known to achieve DC but it's not always guaranteed and the RAM specs have to be the same for it to work.