This is of little importance with real applications, but can matter by a few percent in certain memory-intensive computations. Mixing 4GB and 8GB modules worked OK (but not recommended) Memory bandwidthĪs part of MemoryTester’s output, the memcpy() speed is shown, thus revealing how fast the memory is. When buying and configuring a Mac Pro, be sure to read our step-by-step guide.

This is especially interesting, because as this was written, the quad-core 3.33GHz Mac Pro remained the fastest Mac Pro available for most uses. While few users need 64GB, breaking the 16GB barrier for the quad-core model is/was a big deal, extending the range of file sizes and software that are viable on the quad-core machine.

Using more than 32GB memory requires booting with the 64-bit Snow Leopard kernel, at least with Mac OS X 10.6.2 In December 2009, Other World Computing produced a breakthrough product for Apple Mac Pro Nehalem (2009) users: 8GB memory modules (1066MHz), thus breaking the 16GB memory barrier for the quad-core Mac Pro (4 slots) and allowing 64GB in an 8-core Mac Pro (8 slots). This article is dated, but still applies in general to the 20 Mac Pros.

See also the 16GB memory modules review, which allows even more memory in both 4-core and 6-core Mac Pros. Send Feedback Related: Apple macOS, bandwidth, Mac Pro, memory, Other World Computing, Photoshop