But the link can explain a lot better then I can.
I'm trying to understand how motherboards read dual channel memory. I have a Biostar board (Acer M1100 Desktop) with 4 memory slots. I understand that one set is identified as one channel and the other pair is the 2nd channel. I currently have 2 1GB 667MHz chips in the first set of slots. I added a 3rd 1GB 667 chip in the next open slot and I noticed that the Windows Experience Index in W7 dropped my score down from a 5.5 to a 5.0 after the upgrade. My question is; did putting just one memory chip in the open slot instead of two matching chips cause the MB to revert to single channel access for each chip? I was assuming that the MB would read 2GB on one channel and 1GB on the 2nd channel.
I know that if you have 4 slots on a board that supports DDR3 populated with 4 equal size DDR3 chips, the board will revert to dual channel instead of tripple channel. Wonder if this is the same behavior for Dual channel.
Basically I was wondering if I had to use 4 1GB chips to maintain dual channel performace. Sorry for the long post.