Multiple organs transplant between Mac Mini and Macbook Pro

[monsieurpaul]

Hello all,

I have been using for almost 3 years a Macbook Pro (MBP) 2009 Core 2 Duo 2.66, mainly for coding. Last summer, I did some improvements on it: 8 GB DDR1066 ram, SDD in optibay.

I have just bought a refurbished Mac Mini (mid 2011, 2.5 GHz and 4 GB DDR1333 ram) that I plan to use as my main computer, with the MBP as a Mountain Lion sidekick. I want to transfer the SSD + the 8 GB ram from the MBP to the Mac Mini and the 4 GB ram from the Mac Mini to the MBP.

I am not particularly worried for the SSD: I have check iFixit and the excellent thread in this forum, and I am just waiting my SATA cable. However, I have 2 questions about the ram:
- I understand I can put DDR1066 ram in the Mac mini, but will the lower performance compare to DDR1333 ram be noticeable? What is the best setup: 4 GB DDR1333 or 8 GB DDR1066?
- Can I put DDR1333 ram in a 2009 MBP?

Thanks,

Paul

 

[Darth.Titan]

You're asking for trouble putting wrong speed memory in your computers.

In my experience, you can often get away with putting RAM that's faster than the machine requires, i.e. putting the DDR1333 in the MBP. It obviously won't run at full speed, but there's a possibility it won't work at all.

Putting the DDR1066 RAM in a machine made for DDR1333 likely won't work at all. If it does work, the RAM is going to be overstressed and will likely give out sooner than normal.

There's a reason RAM is sold in different speeds and configurations. They're not supposed to be interchangeable. My recommendation is that if you need more RAM for the Mini, buy the correct type and upgrade instead of switching modules with an older computer. An 8GB kit for the Mini can be had for about $40.

 

[Cap'n Crunch]

Assuming that the Mac Mini reads the SPD values on the RAM and configures itself correctly, it should work fine -- memory bandwidth will just be reduced compared to the stock configuration (DDR3-1333).

The only way to know for sure is to try. If System Profiler reports DDR3-1066 speeds then you know the RAM is only being pushed at 1066 MHz, and thus should be fine. If it reports DDR3-1333 then it's being pushed beyond spec and may or may not be 100% reliable.

Pushing RAM at a speed higher than its rating will not damage it. It will simply result in unreliable operation

 

[monsieurpaul]

Thanks all for your answers.

Considering the really low price of 2 x 4 GB DDR3-1333, it's not worth to transplant the ram between the 2 macs.