64GB -4x16GB Memory Ram Apple Mac Pro 5.1 2010 8-Core and 12-Core all CPU's

Kit Capacity: 64GB. The 8-Core 2.40GHz model will only run the ram @ 1066Mhz. If however you were to upgrade and install a CPU that was capable of running 1333Mhz ram, the ram would then run at 1333Mhz, this is a very useful dormant feature that you can enable in the future when upgrading your CPU.

eBay