Quick Dual Channel Memory question

[Teny]

so im planning to get a new ram, or a new motherboard, but due to my budget, i can only get one for now till about christmas.
so heres the question about dual channel, will having 2 gb on a single channel motherboard run faster than a dual channel motherboard with 1.5 gb?
or does the 1.5 gb dual channel run faster than having the 2 gb single channel?

 

[FlightSimBoy]

You really cant do dual channel with different size RAM. They have to be the same size, like 512 mb and 512 mb, 1 gb and 1 gb, so on and so fourth.
2 gb would outperform 1.5 gb, but not by much. it is worth the extra money if you know you are going to need 2 gb anyway.