Installing Or Replacing A Memory Module - Lenovo ThinkCentre M78 Hardware Maintenance Manual

6. Pivot the optical drive bay upward to access the system board components and the cables. See
"Replacing the optical drive" on page 156.

Installing or replacing a memory module

Attention:
Do not open your computer or attempt any repair before reading and understanding "Important safety information"
on page 1.
This section provides instructions on how to install or replace a memory module.
Your computer has four slots for installing or replacing DDR3 UDIMMs that provide up to a maximum of
32 GB system memory. When installing or replacing a memory module, use 2 GB, 4 GB, or 8 GB DDR3
UDIMMs in any combination up to a maximum of 32 GB.
The following table provides information about the memory module installation rules that you should
consider when installing or removing a memory module. The "X" mark indicates the memory slot(s) into
which the memory module(s) should be installed in different situations. The numbers 1, 2, 3, and 4 indicate
the installation sequence. To locate the memory module slots, see "Locating parts on the system board"
on page 71.
UDIMM
One UDIMM
Two UDIMMs
Three UDIMMs
Four UDIMMs
To install or replace a memory module, do the following:
1. Turn off the computer and disconnect all power cords from electrical outlets.
2. Open the computer cover. See "Opening the computer cover" on page 136.
3. Remove the front bezel. See "Removing and reinstalling the front bezel" on page 136.
4. Remove the heat sink fan duct. See "Replacing the heat sink and fan assembly" on page 100.
5. Remove the hard disk drive. See "Replacing the hard disk drive" on page 151.
6. Pivot the optical drive bay upward to gain access to the memory slots. See "Replacing the optical
drive" on page 156.
7. Locate the memory slots. See "Locating parts on the system board" on page 71.
8. Remove any parts that might prevent access to the memory slots.
9. Depending on whether you are installing or replacing a memory module, do one of the following:
DIMM 1 DIMM 2
X, 3
X, 3
.
Chapter 10 Replacing FRUs (machine types: 2113, 2114, 2115, 3515, 4860, 4863, 4865, 4866,
DIMM 3
X
X, 1
X, 1
X, 1 X, 4
4869, 5100, 10BS, 10BT, and 10BU)
DIMM 4
X, 2
X, 2
X, 2
139