Installing System Components 79

Installing the Cooling Shroud

1
Position the
cooling
shroud by aligning the guide slots with the guide
screws on the system board. See Figure 3-10.
2
Push the
cooling
shroud down until all edges are secured to the system
board.
3
Close the system. See "Opening and Closing the System" on page 62.

System Memory

Your system supports single and dual-rank DDR3 unbuffered ECC DIMMs
(UDIMMs). DIMMs can be 1066 or 1333 MHz.
The system contains four memory sockets. Each two-socket set is organized
into two channels. The first socket of each channel is marked with white
release levers.

General Memory Module Installation Guidelines

To ensure optimal performance of your system, observe the following general
guidelines when configuring your system memory.
NOTE: Memory configurations that fail to observe these guidelines can prevent
your system from starting and producing any video output.
Except for memory channels that are unused, all populated memory
channels must have identical configurations.
Memory modules of different sizes can be mixed in sockets 1 to 4
(for example, 2 GB and 4 GB), but all populated channels must have
identical configurations.
Memory modules are installed in the numeric order of the sockets
beginning with 1 to 4.
One or two DIMMs per channel can support up to 1333
Mhz.
If memory modules with different speeds are installed, they will operate at
the speed of the slowest installed memory module(s).
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