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OWC 16GB Memory Modules for 2009/2010/2011 Mac Pro (2011 variant)
The January, 2012 dual-rank modules run at 1333MHz, and can be expected to perform slightly better than what is shown here.
While few users need more than 32GB memory, some do.

The May 2011 availability of 48GB memory in a 4-memory-slot 2009 or 2010 Mac Pro using 16GB memory modules extends the range of applications, such as working with huge panoramic images.
Users of 12-core Mac Pros have the option of 128GB. For obscure system software reasons, the 4-6/core Mac Pro is limited to 54GB a 3 X 16GB + 1 X 8B modules.
The 4GB, 8GB and 16GB memory modules tested here in this review are all OWC memory, which offers huge savings over Apple memory (and are what your author uses).

Recommendations for maximum memory
Enough is enough— if total memory requirements can be handled with 8GB modules in the optimal 3 or 6 module configurations, stick with that approach.
Note that accessing more than 32GB memory requires booting with the 64-bit kernel with Mac OS X 10.6.x Snow Leopard.
6-core Mac pro
Stick with 3 modules, unless the particular application demands more, as proven by observation of actual memory use.
48GB as 3 X 16GB (OK to add one 8GB module)
12-core Mac Pro
The January 2012 dual-rank 16GB modules work fine as 8 X 16GB = 128GB in an 8-core or 12-cor Mac Pro.
96GB as 6 X 16GB
128GB as 8 X 16GB
Continue reading on the next page.

Apple 16.2" MacBook Pro with M1 Max Chip (Late 2021, Space Gray)
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