mckaybh

Q: Mismatched RAM question

I'm a high school photography teacher with a computer lab of 20 early 2011 iMacs. I recently requested a RAM upgrade from the 4 that came with the machines to 12. I wanted to add 2x4 in the 2 empty slots.

 

Well, the district IT guy had some RAM laying around that he brought over - 20 2gb modules and 20 4gb modules. He recommended installing a 2 and a 4 and each machine for a total of 10 gb. Every online source says "don't mix ram sizes". Apple says to install matched pairs for optimum performance. I know this.

 

My question: will the 10gb setup be better, worse, or equal to an 8gb setup (4x2)? And could I damage the machines by installing 2,2,2,4?

 

I'm wondering if I would be better off with half the machines having 12gb and the other half having 8gb.

 

I searched high and low but couldn't find an answer to this specific question.

imac

Posted on Oct 19, 2016 6:05 PM

Close

Q: Mismatched RAM question

  • All replies
  • Helpful answers

  • by pokey b,

    pokey b pokey b Oct 19, 2016 6:27 PM in response to mckaybh
    Level 3 (679 points)
    Desktops
    Oct 19, 2016 6:27 PM in response to mckaybh

    I have experience with only one i-Mac, a mid-2010, 21.5 inch i-Mac. About a year ago I added 8 GB of OWC RAM to the original 4 GB that was in the Mac. It works great for me. The recommendations that I hear over and over again here on this forum are to use only top quality RAM as Macs are finicky about RAM. I'm not sure I would trust a hand full of RAM that someone brings over. Only OWC and Crucial RAM are typically recommended. I have installed the RAM as indicated below. I left the original RAM where it was, and installed the new RAM in the empty slots.

     

    Ram Installed.png

  • by mattwithcats,

    mattwithcats mattwithcats Oct 19, 2016 8:15 PM in response to mckaybh
    Level 1 (50 points)
    Desktops
    Oct 19, 2016 8:15 PM in response to mckaybh

    First, ten of the machines can use the two 4 gig OEM chips removed from the other ten machines.

    Presto, ten machines with 8 gigs (four 2 gig Apple chips)

    This reduces your problem to ten computers.

     

    Now lets tackle the twenty 4 gig chips...

    Look at them closely, what name is on them, and what numbers?

    Google these numbers, and compare the specs to the OEM specs, drill down from here...

    http://www.datamemorysystems.com/apple-imac-intel-memory-upgrades/

     

    If all looks good, remove the OEM ships, install one pair, and try to boot the machine.

    Three "bongs" means the memory is incompatible.

     

    Do the same thing for the twenty 2 gig chips,

    look up as much info on them as you can,

    compare the specs,

    and if they match, do a test run.

     

    Now install two 4 gig chips side by side, and then two 2 gig chips side by side..

    Test boot the computer, look to see if it has 12 gigs.