1600mhz ddr3 macbook pro ram in 1066mhz ddr3 macbook pro

costeta

macrumors member
Original poster
Jul 24, 2008
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420
I've a 2012 macbook pro with 8gb (4x2) 1600mhz ddr3 ram. I also have a 2010 macbook pro with 4gb (2x2) 1066mhz ram. I want to upgrade the 2010 mbp to 8gb and the 2012 to 16gb, but I would rather put the 2012 1600mhz ram into the 2010, and order a new 16gb ram for the 2012 mbp, and save some money. Will the 1600mhz ram work in the 2010 mbp even though it's specification is 1066mhz?
 

Patcell

macrumors 6502
Aug 8, 2016
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Bergen County, NJ
It should work just fine. The 1600mhz sticks will just run at 1066mhz in the 2010 machine; that is the frequency the logic board supports. No reason it would cause any harm though.
 

keysofanxiety

macrumors G3
Nov 23, 2011
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24,228
I'm surprised to read the advice above because I've found they just won't work. The first gen i processors are properly picky with RAM. The 2011/2012s are much more versatile with different RAM speeds.

It'll just beep on startup or constantly kernel panic if you fitted the 1600s in the 2010.
 

Patcell

macrumors 6502
Aug 8, 2016
428
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Bergen County, NJ
I'm surprised to read the advice above because I've found they just won't work. The first gen i processors are properly picky with RAM. The 2011/2012s are much more versatile with different RAM speeds.

It'll just beep on startup or constantly kernel panic if you fitted the 1600s in the 2010.
Perhaps I stand corrected... Admittedly, I have only done this with desktop Windows machines, but my experience is that the mother board will work with faster RAM, simply at a lower speed.

I apologize in advance if I was mistaken.
 

keysofanxiety

macrumors G3
Nov 23, 2011
9,472
24,228
Perhaps I stand corrected... Admittedly, I have only done this with desktop Windows machines, but my experience is that the mother board will work with faster RAM, simply at a lower speed.

I apologize in advance if I was mistaken.
No no, not to worry — you're absolutely right about DDR3 RAM underclocking, but the first gens are pretty much the only exception to the rule. They're properly stubborn little things! You'll find the same issue in 1st gen i processors on Windows laptops too, so it's not just limited to MacBooks.

Sorry if I came across as a little blunt. :)
 

Patcell

macrumors 6502
Aug 8, 2016
428
177
Bergen County, NJ
No no, not to worry — you're absolutely right about DDR3 RAM underclocking, but the first gens are pretty much the only exception to the rule. They're properly stubborn little things! You'll find the same issue in 1st gen i processors on Windows laptops too, so it's not just limited to MacBooks.

Sorry if I came across as a little blunt. :)
Not at all! I just don't want to give out bad information... Thanks for the info!
 

costeta

macrumors member
Original poster
Jul 24, 2008
89
420
I tried it. I put the 8gb from 2012 into the 2010. It didn't work.
 

costeta

macrumors member
Original poster
Jul 24, 2008
89
420
Sorry about that... As keysofanxiety explained, it looks like the memory controller will not under-clock the faster RAM.
Yeah no problem. I think that might be the issue. I've read from somewhere where other people have had success with over-clocked rams, but it must be system specific.
 

T5BRICK

macrumors G3
Aug 3, 2006
8,086
2,055
Oregon
The 2010 models are pretty picky about RAM.

I had a 2009 13" MBP, and it worked with 1333MHz RAM, but not the 1600MHz stuff.