Chosen Solution

Hi! Do I need normal DDR3 or the lower voltage DDR3L RAM for my mid-2012 Macbook Pro? Everyone says something different. Thanks in advance!

Best answer here is to use what Apple documents: MacBook Pro: How to remove or install memory. Here’s what Apple states: MacBook Pro (13-inch, mid 2012) Number of memory slots 2Base memory 4 GBMaximum memory 8 GB Memory card specifications: Double Data Rate Small Outline Dual Inline Memory Module (DDR3) format67.6mm x 30mm (1.18 inch)2 GB or 4 GB204-pinPC3-12800 DDR3 1600 MHz type RAM Additional notes: For best performance, fill both memory slots, installing an equal memory module in each slot. I should point out this listing is a bit dated as this series can support 8 GB modules so you can go up to 16 GB of RAM.

I would not agree that the best answer is to consult Apple, since Apple is famous for not letting ppl know, how their devices actually work. You see that already in the short portion, Dan posted here: The Maximum memory capacity of these machines is NOT 8 GB. 16 GB works just fine, Apple just never tested it so they never shared this information. As for DDR3L and DDR3: I also was not sure, so I tested it: Both work without a problem, so you can install both. As for, if it makes a difference: The Power Rail for the RAM is called “PP1V5S3_DDR”, stating it as a 1.5 V rail. I installed DDR3L modules and still the voltage on the rail was 1.506 V. So even though the modules could run on 1.35 V, the logic board always runs them on 1.5 V since that is what it’s designed for. This was tested with the most recent Catalina update, so with the most recent EFI. This is not rocket since, but I could not find this definitive answer anywhere on the web, so I checked for myself and posted it here.

@danj It can run 16gb Max Ram too

so besides the voltage does the older high 1.5v make it better or running a lower ddr3l make the MB run better and faster? Also does cl 11 mean anything in terms of fastness and cycle time 1.875??