Lenovo ThinkCentre M90t, User Manual

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Static electricity prevention
Static electricity, although harmless to you, can seriously damage computer components and options.
Improper handling of static-sensitive parts can damage the part. When you unpack an option or CRU, do not
open the static-protective package containing the part until the instructions direct you to install it.
When you handle options or CRUs, or perform any work inside the computer, take the following precautions
to avoid static-electricity damage:
• Limit your movement. Movement can cause static electricity to build up around you.
• Always handle components carefully. Handle adapters, memory modules, and other circuit boards by the
edges. Never touch exposed circuitry.
• Prevent others from touching components.
• When you install a static-sensitive option or CRU, touch the static-protective package containing the part
to a metal expansion-slot cover or other unpainted metal surface on the computer for at least two
seconds. This reduces static electricity in the package and your body.
• When possible, remove the static-sensitive part from the static-protective packaging and install the part
without setting it down. When this is not possible, place the static-protective packaging on a smooth, level
surface and place the part on it.
• Do not place the part on the computer cover or other metal surface.
Operating environment
Maximum altitude (without pressurization)
• Operating: From -15.2 m (-50 ft) to 3048 m (10 000 ft)
• Storage: From -15.2 m (-50 ft) to 10 668 m (35 000 ft)
Temperature
• Operating: From 10°C (50°F) to 35°C (95°F)
• Storage in original shipping package:
– For common desktop computers: From -40°C (-40°F) to 60°C (140°F)
– For all-in-one desktop computers: From -20°C (-4°F) to 60°C (140°F)
• Storage without package: From -10°C (14°F) to 60°C (140°F)
Note: If your computer is stored or transported in temperatures less than 10°C (50°F), allow the computer to
rise slowly to an optimal operating temperature before use. This process might take up to two hours. Using
the computer in a lower operating temperature might result in irreparable damage to your computer.
Relative humidity
• Operating: 20%-80% (non-condensing)
• Storage: 20%–90% (non-condensing)
Cleaning and maintenance
With appropriate care and maintenance, your computer will serve you reliably. The following topics offer
information to help you keep your computer working with best performance.
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M90t User Guide