OWC OWC1866D3R9M64 64GB Memory Upgrade Kit

OWC Memory for Mac Pro 2013 fully meets Apple's specifications with special attention to proper thermal specifications.

Note: Apple Mac Pro 2013 models utilizes ECC non-Registered for 4GB and 8GB per slot options and ECC Registered for 16GB (and larger) per slot options. Any existing 4GB and 8GB ECC non-Registered modules cannot be mixed with 16GB and larger ECC-Registered modules and will need to be removed in order to utilize these higher density memory upgrade options.