HP Z220 SFF, Z220 CMT, Z420, Z620, and Z820 Workstations Maintenance and Service Guide

HP Z620 Workstation DIMM installation order
Install DIMMs in this order.
NOTE: If you install DIMMs of different sizes, load them in order of size, starting with largest and
finishing with the smallest (largest in DIMM 1, smallest in last loaded DIMM).
102 Chapter 3 Component replacement information and guidelines