This Memory is only recommended for experienced technicians!
Up to 128GB OWC Memory For all iMac Pro 2017 Models:
Apple 2017 iMac Pro 2.3GHz 18-Core Xeon
Apple 2017 iMac Pro 2.5GHz 14-Core Xeon
Apple 2017 iMac Pro 3.0GHz 10-Core Xeon
Apple 2017 iMac Pro 3.2GHz 8-Core Xeon
*64GB memory modules are for 2 slots only. 64GB memory modules in all 4 slots is not supported by Apple at this time. The other 2 slots will remain empty, and could be used at a later date if the 128GB memory limit is removed by Apple.