Populating Dimm Sockets; Installing Dimms - HP Compaq Pro 4300 Maintenance And Service Manual

Populating DIMM Sockets

There are two DIMM sockets on the system board: XMM1 and XMM3 with one socket per Channel.
XMM3 operates in memory channel A. XMM1 operates in memory Channel B.
The system will automatically operate in single channel mode, dual channel mode, or flex mode,
depending on how the DIMMs are installed.
●
The system will operate in single channel mode if the DIMM sockets are populated in one
channel only.
●
The system will operate in a higher-performing dual channel mode if the total memory capacity
of the DIMM in Channel A is equal to the total memory capacity of the DIMM in Channel B.
●
The system will operate in flex mode if the total memory capacity of the DIMM in Channel A is
not equal to the total memory capacity of the DIMM in Channel B. In flex mode, the channel
populated with the least amount of memory describes the total amount of memory assigned to
dual channel and the remainder is assigned to single channel. If one channel will have more
memory than the other, the larger amount should be assigned to Channel A.
●
In any mode, the maximum operational speed is determined by the slowest DIMM in the system.

Installing DIMMs

CAUTION:
to drain before adding or removing memory modules. Regardless of the power-on state, voltage is
always supplied to the memory modules as long as the computer is plugged into an active AC outlet.
Adding or removing memory modules while voltage is present may cause irreparable damage to the
memory modules or system board.
The memory module sockets have gold-plated metal contacts. When upgrading the memory, it is
important to use memory modules with gold-plated metal contacts to prevent corrosion and/or
oxidation resulting from having incompatible metals in contact with each other.
Static electricity can damage the electronic components of the computer or optional cards. Before
beginning these procedures, ensure that you are discharged of static electricity by briefly touching a
grounded metal object.
When handling a memory module, be careful not to touch any of the contacts. Doing so may damage
the module.
1. Prepare the computer for disassembly
2. Remove the access panel
44 Chapter 7 Removal and Replacement Procedures Small Form Factor (SFF) Chassis
You must disconnect the power cord and wait approximately 30 seconds for the power
(Computer Access Panel on page
(Preparation for Disassembly on page
39).
37).