Increasing RAM in late 2009 iMac. Installed two - 4 gig sticks in slots 1 and 2 and all is fine. Installed second pair of 4 Gig sticks to slots 3 and 4 and iMac now does not boot up (it just beeps). Similar problem on second iMac using 2 gig sticks.
iMac
Be sure the memory meets the computer's specs:
| Maximum Memory | 16 GB |
|---|---|
| Memory Slots | 4 - 204-pin PC3-8500 (1066 MHz) DDR3 SO-DIMM |
Memory should be installed in matched pairs in adjacent slots. Two slots on the top and two slots on the bottom.
Be sure the modules are inserted properly. They should "click" or "crunch" into the slots. You may have to push hard.
Everything was matched. First computer I tried had 2 x 2 Gig memory sticks and it works fine with only the two top slots filled. Then I added another pair of of 2 gig memory sticks and the problem of not booting and just beeping happened. Tried on a different computer using 4 gig memory sticks and exactly the same problem occurred. Works fine with one pair of 4 gig sticks in the top two slots, fails to boot and just beeps when the second pair of 4 gig memory sticks is added. Everthing is seated properly (unless there is an issue with the bottom slots from years of non-use. Wouldn't think a dust buildup would cause a failure. The OS is obviously sensing the slots are being used and, for some reason, it isn't able to deal with the additional memory. I am not above the manufacturers specs for memory for these machines. They are definitely late 2009 builds. Any other suggestions would be most appreciated.
I would clean the slots. You may also want to use a clean pencil eraser and clean the edge-card pins on both sides. Beyond that all I can suggest is to contact the memory vendor and ask for replacements.
Have you tried moving the modules that are working in the top slots to the bottom ones? You know that memory is good. If it doesn't get recognized in the bottom slots, then it's a slot problem.
Dadiohead,
What model and brand of RAM did you buy? Imacs are extremely RAM, most experienced users on these forums only recommend using OWC (www.macsales.com) or Crucial.
Macs are finicky. Therefore I am using Kingston RAM that was purchased from Crucial.
I have done some mixing and matching. I took working 2Gig RAM from the top slots of one iMac and inserted them in the bottom two slots of a second iMac. Nadda. I will get in there and clean it all out and see if that makes the connection. Thanks for the eraser tip.
Dadiohead wrote:
Macs are finicky. Therefore I am using Kingston RAM that was purchased from Crucial.
Kingston RAM has a long history of having problems, particularly their value RAM. If your problem continues, return the Kingston and purchase Crucial RAM directly from Crucial.
Understood. But this same problem happened with two x 2 Gig memory sticks that came out of one of the other iMacs I was upgrading. This was OEM RAM and when I inserted it in to the other iMac, same non-boot and warning sound. So it happened twice, with two different computers using two different kinds of RAM from two different manufacturers. I'm not persuaded it's the RAM.
Increasing RAM in late 2009 iMac
