Installing Dimms - HP 280 G4 MT Maintenance And Service Manual

● The system will operate in flex mode if the total memory capacity of the DIMMs in Channel A is not equal to
the total memory capacity of the DIMMs 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. For optimal speed, the channels should be balanced so that the largest amount
of memory is spread between the two channels. If one channel will have more memory than the other, the
larger amount should be assigned to Channel A. For example, if you are populating the sockets with one 2-
GB DIMM, and three 1-GB DIMMs, Channel A should be populated with the 2-GB DIMM and one 1-GB DIMM,
and Channel B should be populated with the other two 1-GB DIMMs. With this configuration, 4-GB will run
as dual channel and 1-GB will run as single channel.
● In any mode, the maximum operational speed is determined by the slowest DIMM in the system.

Installing DIMMs

CAUTION: You must disconnect the power cord and wait approximately 30 seconds for the power 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
3. Open both latches of the memory module socket (1), and insert the memory module into the socket (2).
NOTE:
on the memory socket.
Populate the XMM1 socket before the XMM2 socket.
(Access panel on page
A memory module can be installed in only one way. Match the notch on the module with the tab
(Preparation for disassembly on page
17)
16)
Memory 23