Lenovo B450 User Manual page 101

Your computer contains the following types of internal CRUs:
• Internal CRUs (located behind an access panel): These CRUs are
isolated parts within the computer that are concealed by an access panel
that is typically secured by either one or two screws. Once the access
panel is removed, only the specific CRU is visible. Examples of these
types of CRUs include memory modules and hard disk drives.
• Internal CRUs (located within the product): These CRUs are accessible
only by opening the computer's outer case. Examples of these CRUs
include PCI Express Mini Cards and the integrated keyboard.
Appendix D. Customer replaceable units (CRUs)
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