Quote Originally Posted by Buckster View Post
question please - if I upgrade my 2x 1 gig RAM modules and add 2x 512MB ... will I still keep dual channel ?

does RAM have to be the same size in each bank or overall all 4 slots ?

thanks, Mark.
On the P65 (particularly Asus P5B Deluxe), if all four all slots are filled, and they are different sizes, the BIOS will map the lowest stick and use the same amount of the larger sticks as Dual channel operation. Whatever amount is remained will be used as single channel. There is a page on the manual that talks about such. To minimize any problem, though, make sure all the sticks use or can use the same timing. The manual suggests this as well.