Dell OptiPlex N, Руководство пользователя

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2-2 Dell OptiPlex N and OptiPlex NX Systems User’s Guide
Cleaning the Computer, Monitor, and
Keyboard Exteriors
1. Turn off the computer, the monitor, and any
attached peripherals, and disconnect them from
their power sources.
2. Use a vacuum cleaner to remove any dust from
the slots and holes on the computer and between
the keys on the keyboard.
3. Moisten a soft cleaning cloth with a dishwashing
detergent solution, and use the cloth to wipe the
computer cover, the keyboard, and the exterior of
the monitor, including the screen.
Do not soak the cloth in the solution; you must not
let the solution drip inside the computer or the key-
board. If you get moisture into any of the computer
components, contact your network administrator
immediately.
M
inimizing Environmental
Hazards
This section discusses various environmental factors that
can adversely affect system performance and longevity.
Temperature
Temperature extremes can cause a variety of problems,
including premature aging and failure of chips and
mechanical failure of devices. Extreme temperature fluc-
tuations can cause chips to become loose in their sockets
and can cause expansion and contraction of disk drive
platters, resulting in read or write data errors.
There are several guidelines you can follow to minimize
the negative effects of temperature on system
performance.
For optimum system performance, follow these
guidelines:
•
Operate the system in an environment no colder than
10
°
Celsius (C) (50
°
Fahrenheit [F]) or hotter than
35
°
C (95
°
F).
NOTE: At 35
°
C (95
°
F), the maximum operating alti-
tude is 914.4 meters (m) (3,000 feet [ft]).
•
Ensure that the system has adequate ventilation.
Make sure that all slots and openings on the com-
puter remain unobstructed, especially the fan vent on
the front of the computer.
Do not place the system within a closed-in wall unit
or on top of cloth material, which can act as insula-
tion. Do not place it where it will receive direct
sunlight. Do not place it next to a heat source of any
kind, including heating vents during the winter.
•
Clean the system at regular intervals to avoid any
buildup of dust and debris, which can cause a system
to overheat.
•
If the system has been exposed to abnormally cold
temperatures, allow a 15-minute warm-up period
before it is turned on and starts attempting to read
from or write to the hard-disk drive.
•
If you notice intermittent system failures, ask your
network administrator or a service technician to
reseat any socketed chips, which might have become
loose because of temperature fluctuations.
Humidity
High-humidity conditions can cause moisture to collect
in the computer. This moisture can cause corrosion of
internal components and degradation of properties such
as electrical resistance, thermal conductivity, physical
strength, and size. Extreme moisture buildup inside the
computer can result in electrical shorts, which can cause
serious damage to the computer.
Each Dell system is rated to operate at 20 percent to
80 percent relative humidity, with a humidity gradation
of 10 percent per hour. In storage, a Dell system can
withstand from 5 percent to 95 percent relative humidity.
Buildings in which climate is controlled by air-
conditioning in the warmer months and by heat during
the colder months usually maintain an acceptable level of
humidity for computer equipment. However, if a system
is located in an unusually humid location, use a dehumid-
ifier to maintain the humidity within an acceptable range.
Altitude
Operating a system at high altitude (low pressure)
reduces the efficiency of forced and convection cooling
and can result in electrical problems related to arcing and