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 memory capacity of the DIMM in Channel A is equal to the memory capacity of the DIMM in Channel B.

The system will operate in flex mode if the memory capacity of the DIMM in Channel A is not equal to the 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: 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. For more information, refer to Electrostatic discharge on page 25.

When handling a memory module, be careful not to touch any of the contacts. Doing so may damage the module.

1.Remove/disengage any security devices that prohibit opening the computer.

2.Remove all removable media, such as optical discs or USB flash drives, from the computer.

3.Turn off the computer properly through the operating system, then turn off any external devices.

4.Disconnect the power cord from the power outlet and disconnect any external devices.

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.

5.Remove the computer access panel.

WARNING! To reduce risk of personal injury from hot surfaces, allow the internal system components to cool before touching.

Installing additional memory

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