can i mix differnt ram sizes with Dual-channel memory architecture?

[911aaron]

Hey guys.
I'm upgrading my girlfriends computer with extra ram. She already has 1, 512mb ddr2 533 (pc2-4200) stick in her computer.
I want to buy her
http://www.newegg.com/Product/Produ...043&cm_re=4200_g.skill-_-20-231-043-_-Product
which is 1GB DDR2 533 (PC2 4200) for her computer, but im wondering if this will work because they are different sizes. i have read that it doesnt matter what size they are as long as they have the same speed and latency, but i also read that if the mobo has Dual-channel memory architecture, then the two sticks MUST be the same. If that is true, then am i not allowed to have both sticks in at the same time to have a total of 1.5gb of ram?

Just would like anyone to clear up any false statements, if any. I appreciate any response

 

[johnb35]

You can get that memory it just won't run in dual channel.

 

[911aaron]

so i can put both sticks in at the same time for a total of 1.5gb ram right?

and if i do put them in, do i put it in like this?

-A------B------A-------B
512----------1024------

or like this

-A------B------A-------B
512---1024-------------

 

[johnb35]

Usually the same channel slots are the same color. You want A and A or B and B but not A and B.