Chosen Solution
Yesterday, I went to the local MicroCenter store to purchase a memory upgrade kit for my MacBook Pro 15" unibody mid-2012 edition. I have installed 2 8GB RAM memory modules, but the MacBook is only recognizing 1 of them. Can anyone help determine why only 1 of the 2 modules is being recognized? I am out of luck? Is it possible that I didn’t securely seat 1 of the 2 modules in the computer? After looking at other posts, I can confirm the following about my MacBook Pro: Model Identifier: MacBookPro9,1 Boot ROM Version: MBP91.00D3.B0E SMC Version: 2.1f175 So, I have confirmed that I am running the latest firmware, etc. per the question asked and answered here: Install fully functional 16gb ram on my MacBook model 7,1? I installed Crucial brand memory manufactured by Micron and designed for the Mac. The kit includes 2 8GB DDR3L-1600 SODIMM 1.35V CL11 memory modules. Crucial Web site actually shows that this should be compatible as well though the “model number” of the RAM they are currently selling differs from what I bought. My Crucial Memory model #: CT2C8G3S160BM The compatible model # on Crucial Web site: CT3327432
Jaygrn, Sounds like a seating issue. I would remove and replace the sticks in reverse order ie place the top stick securely in the bottom position and the current bottom stick in the upper slot, ensuring that they are fully engaged and sound. Hope you get it sorted. Let me know if this resolves the issue. Andrew