Matching Memory?

Discussion in 'Mac Basics and Help' started by hewcardpacklet, Jul 2, 2008.

  1. hewcardpacklet macrumors member

    Mar 19, 2008
    Montreal Canada
    On my iMac I have the original 1GB memory chip, and I have added a 2GB memory chip from - the specs are the same: DDR2 SDRAM 667 MHz. The machine seem to behave correctly, very stable and fast.

    However, I have read in some posts some people recommending to match the memory - have 2 1GB chips, or 2 2GB chips - they say that if they don't match, it affects speed and reliability...

    Is it true, or are those saying that inventing stuff to look smart? Any expert would like to comment?
  2. CanadaRAM macrumors G5


    Oct 11, 2004
    On the Left Coast - Victoria BC Canada
    If you have matching memory ( 2 x 1 GB or 2 x 2 GB ) then the machine can implement dual-channel memory access. That's good for about a 6% - 8% increase in performance - nice to have, but certainly not necessary.

    However, overall having three GB totall (unmatched) is more of an advantage than limiting yourself to two GB with matching RAM.

    If you're feeling flush, the ultimate is to go with a pair of 2 GB to get both the extra RAM and the small % boost. (you get the benefit of dual-channel access even if you have an earlier model Core2Duo that can only let OSX address 3 GB)

Share This Page