Lenovo ThinkStation 2551 Hardware Maintenance Manual page 100

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. Remove the computer cover. See "Removing the computer cover" on page 88.
3. Lay the computer on its side for easier access to the system board.
4. Locate the memory slots. See "Locating parts on the system board" on page 76.
5. Remove any parts that might prevent your access to the memory slots. Depending on your computer
model, you might need to remove the PCI Express x16 graphics card for easier access to the memory
slots. See "Installing or replacing a PCI card" on page 90.
6. Depending on whether you are installing or replacing a memory module, do one of the following:
• If you are replacing an old memory module, open the retaining clips and gently pull the memory
module out of the memory slot.
Figure 17. Removing a memory module
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ThinkStation Hardware Maintenance Manual
DIMM 1 DIMM 2
X, 3
X, 3
DIMM 3
X
X, 1
X, 1
X, 1 X, 4
DIMM 4
X, 2
X, 2
X, 2