Upgrade the memory in your 2013 Mac Pro (MacPro6,1) using the 64GB DDR3 1866 MHz RDIMM Memory Kit from OWC / Other World Computing. This memory kit features a total capacity of 64GB, which is made up of four 16GB modules. It also has a clock speed of 1866 MHz, a bus speed of PC3-14900, and a 240-pin RDIMM form factor. It operates using 1.5V, has a CAS Latency of CL=13, a module bandwidth of 14.9 GB/s, a component configuration of 2048M x 72, is registered, and is equipped with ECC technology. Registered memory places less electrical loads on the memory controller and allows single systems to remain stable with more memory modules than they would have otherwise. By offering ECC (Error Checking and Correcting) technology, this RAM will help your workstation encounter fewer errors that can corrupt data sets and introduce system issues. Additionally, this memory module is compatible with Apple Specified Thermal Sensor, which ensures that the RAM maintains a safe thermal operating range.
IMPORTANT: Mac Pro (Late 2013) models utilize thermal enabled ECC Registered and ECC non-Registered memory, however ECC Registered and ECC non-Registered memory cannot be combined. If you are adding ECC Registered memory in a system with ECC non-Registered memory, you will need to remove the original ECC non-Registered memory prior to installing the ECC Registered memory.
