So I recently got me some memory for my Mid 2010 iMac. I knew for a fact that my iMac used DDR 3 laptop memory. I also made sure that the memory met the specification below before buying it.
So I opened it up and found some samsung memory(which was already in the iMac), which totaled 4GB(2 sticks of 4GB. I inserted the corsair memory and booted up the machine. It worked for a few hours and then it froze and emitted 3 loud beeps.
What is going on here? Is it possible that I need to use the same brand of memory in the machine?
Please reply soon, Adiman423
Answer by Griff · Oct 14, 2011 at 03:59 PM
It sounds like you got a bad set of RAM. A 3 beep error code on an iMac means "No RAM banks passed memory testing." It failed during its 'Power On Self Test.'
I would advise you to remove the Corsair RAM and have it replaced from either the company you bought it from, or Corsair themselves. The Samsung RAM should work just fine, and while there is no official rule saying you shouldn't mix different brands of RAM, it is common practice for some geeks to install matching sticks to ensure maximum compatibility.