Dell Inspiron 13z (N311z, Mid 2011) - Manual (Page 19)

Memory 19
NOTE: If the memory module is not installed properly, the computer may not boot.
4 Replace the module cover. See "Replacing the Module Cover" on page 16.
5 Replace the battery as per the instructions in "Replacing the Battery" on
page 14 or connect the AC adapter to your computer and an electrical
outlet.
6 Turn on the computer.
As the computer boots, it detects the memory module(s) and automatically
updates the system configuration information.
To confirm the amount of memory installed in the computer:
Click Start
Control PanelSystem and Security System.
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