Q: Late 2009 Imac 27" will NOT accept 16gb of pc3-8500 1066mhz ram
I have attempted to install 16gb of pc3-8500 1066mhz ram . I have tried 2 different brands of ram and the same thing happens .....When all 4 sticks of 4gb ram are installed 3 beeps followed by a blank screen.
iMac, iOS 9.1
Posted on Nov 12, 2015 4:27 PM
You're trying to use what I refer to as bargain basement ram, the specs are close but not exact. This is proven by the fact that you can install one of the original sticks with three of the incompatible sticks and it will work. The one original stick allows the computer to read the correct spec and slow the other ones down to a speed that will run, without that original stick the computer reads all wrong speeds. Close enough ram works well in PC's but not Macs. Return the incompatible ram and get ram from OWC as mentioned above.
Posted on Nov 12, 2015 6:16 PM