The late 2013 Apple Mac Pro supports up to 128GB of 1866MHz DDR3 unregistered ECC-DIMM and registered DIMM, using a four-channel memory controller.
1.Registered DIMMs cannot be mixed with unregistered ECC-DIMMs.
2.Due to Intel's Xeon CPU limitation, the system will run at 1066Mhz when installed a quad rank memory module.
3.Due to the mechanical design, the late 2013 Mac Pro cannot use the memory modules with heat sinks and VLP (Very Low Profile) type.
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