Memory module slot, Channel B
Memory module slot, Channel A
The system will automatically operate in single-channel mode, dual-channel mode, or flex mode, depending
on how the memory modules are installed.
The system will operate in single-channel mode if the memory module slots are populated in one
The system will operate in a higher-performing dual-channel mode if the memory capacity of the
memory module in Channel A is equal to the memory capacity of the memory module in Channel B.
The system will operate in flex mode if the memory capacity of the memory module in Channel A is not
equal to the memory capacity of the memory module 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 memory module in the
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
The memory module slots 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. For more information, see
When handling a memory module, be careful not to touch any of the contacts. Doing so may damage the
Prepare the computer for disassembly
Remove the access panel
System Board Label
Electrostatic discharge information on page
(Preparation for disassembly on page
(Access panel on page