HP 9000 Series Service Manual page 174

Dx50/Dx60 Front Panel LCD Codes
Memory SIMMs are not installed in the proper sequence. The Boot
command has been disabled to prevent thermal damage. Refer to the
memory configuration label for proper sequence.
Memory has been reconfigured due to a physical change or because the
Page Deallocation Table (PDT) was cleared. This is for information
only. No action is required.
Memory banks deallocated due to a SIMM size mismatch or a SIMM
failure. Refer to the ME command in the INFORMATION menu for error
information.
5-32 Chapter 5