HP Z440, Z640, and Z840 Workstation Series - Maintenance and Service Guide

Designator Name on board Component
SW3 Rear Power Switch Rear power button/LED
SW50 CMOS Clear CMOS button
XBT1 BAT Battery
XMM1 CPU0-DIMM8 CPU0 Memory DIMM8
XMM2 CPU0-DIMM7 CPU0 Memory DIMM7 (not loaded on Z640)
XMM3 CPU0-DIMM6 CPU0 Memory DIMM6
XMM4 CPU0-DIMM5 CPU0 Memory DIMM5 (not loaded on Z640)
XMM5 CPU0-DIMM1 CPU0 Memory DIMM1
XMM6 CPU0-DIMM2 CPU0 Memory DIMM2 (not loaded on Z640)
XMM7 CPU0-DIMM3 CPU0 Memory DIMM3
XMM8 CPU0-DIMM4 CPU0 Memory DIMM4 (not loaded on Z640)
HP Z440 and Z640 Workstation system board designators 117