In a blog post published last week, Other World Computing unravels a mystery that has seen conflicting information over whether "Late 2008" aluminum MacBooks and MacBook Pros support a maximum of 8 GB of RAM. According to the report, Apple apparently quietly changed a December 2009 firmware update for the machines at some point to boost maximum RAM support from 6 GB to 8 GB.
The discovery comes after numerous reports, including some in our own forums, pointed to 8 GB of RAM being supported in these machines even though OWC's earlier testing had clearly shown that a maximum of 6 GB could be addressed even with 8 GB installed.
Not being the type to just let these sorts of claims to go unchallenged, we went back to our testing lab, grabbed the affected model machines, running 10.6.6. and dropped an 8GB upgrade kit in them.
The results were exactly the same as in 2009, lending credence to our conclusions, but the sheer number of claims to the contrary led us to continue searching - and the trail ended at Apple.
In late 2009, an EFI Firmware Update was released to address the buzzing noises coming from the optical drive. However, it seems that somewhere along the line, Apple changed this update without notating it anywhere.
The MacBook and MacBook Pro EFI firmware updates were issued in December 2009 as part of package to address noise from the optical drive, but were altered at some point after their initial release to also introduce support for a maximum of 8 GB of RAM for users running Mac OS X Snow Leopard.
Consequently, OWC recommends that users of Late 2008 MacBooks and MacBook Pros interested in upgrading to 8 GB of RAM check System Profiler on their machine to determine whether they are running the latest Boot ROM versions of MBP51.007E.B05 (MacBook Pro) or MB51.007D.B03 (MacBook), and if not, re-download the EFI firmware update and apply it to their machines.
Affected machines introduced in late 2008 include MacBooks running at 2.0 GHz and 2.4 GHz, as well as 2.4GHz 15" MacBook Pros and 2.53 GHz and 2.8 GHz MacBook Pro models offering ExpressCard slots.
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Top Rated Comments
So you're saying Apple has done something non-dastardly for a change? Wow.
Let's hope they even lifted the "No 64-bit Windows in bootcamp" limitation they heinously manufactured in certain non-pro MacBooks, like my Late '08 2.4 Unibody that runs 64bit Mac OS X and Ubuntu without a problem.
(One product cycle later they add "Pro" and a FW port to what is essentially the same machine and MAGICALLY bootcamp will install 64bit drivers for Win7.)
Since they'll buy-back my original 2 x 1GB Apple chips as well as my 2 X 2GB OWC's, the net cost is $77, not bad for their excellent customer support.
I can easily max 4GB with just Safari, EW's Multisim and some Pages working. Trust me, I need the 8GB and my Collector's Edition MacBook will be happy to get this update.
As a developer, running our web app and my development environment, I'm maxing out 8GB of RAM fairly frequently. Were I also running our DB (which would have to be silo'd off in a VM running Windows as Oracle no longer supports OS X) 12GB RAM would be necessary, min.
My wife's machine has 4GB RAM and Flash enabled, and frequently starts showing 3.9GB+ "used" memory and things start stuttering. Hers will be getting an 8GB upgrade soon (and Click2Flash perhaps as well ...).
That would be such absolute BS but it wouldn't surprise me at all. "Oh, you want to be able to use more RAM in your Mac? Well that wasn't advertised when we sold it to you, so in order to be able to do that you'll need to hand over $1".