Cleaning Drives
You can clean the heads of your diskette drives by using a commercially available diskette-drive head-cleaning kit. These kits
include diskettes pretreated with a chemical solution to nonabrasively remove contaminants that accumulate on the drive heads
during normal operation.
If the kit does not contain instructions, insert one of the pretreated diskettes into a diskette drive and turn on the system. After 20
or 30 seconds, remove the diskette from the drive. Repeat this procedure for each diskette drive in the computer.
CAUTION:
Do not attempt to clean drive heads with a swab. You may accidentally misalign the heads, rendering
the drive inoperable.
Environmental Factors
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 or mechanical failure of
devices. Extreme temperature fluctuations 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. When you perform a low-level format operation on a hard-
disk drive, it is important to ensure that the drive's surrounding temperature is at or near the temperature at which the drive will be
operated. Failure to do so can result in relocation of the tracks on the disk platters.
To minimize the negative effects of temperature on system performance, follow these guidelines:
Ensure that the system is operated in an environment no colder than 10° Celsius (C) (50° Fahrenheit [F]) or hotter than
35°C (95°F).
Ensure that the system has adequate ventilation. Do not place it within a closed-in wall unit or on top of cloth material,
which can act as insulation. Do not place it where it will receive direct sunlight, particularly in the afternoon. Do not place it
next to a heat source of any kind, including heating vents during winter.
Adequate ventilation is particularly important at high altitudes. System performance may not be optimum when the system is
operating at high temperatures as well as high altitudes.
Make sure that all slots and openings on the computer remain unobstructed, especially the fan vent on the back of the
computer.
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 two-hour warm-up period to bring it up to normal
operating temperature before turning it on. Failure to do so may cause damage to internal components, particularly the hard-
disk drive.
If intermittent system failures are noticed, try reseating any socketed chips, which might have become loose due to
temperature fluctuations.
Humidity
High-humidity conditions can cause moisture migration and penetration into 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 to 80 percent relative humidity, with a humidity gradation of 10 percent per hour. In
storage, a Dell system can withstand from 5 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, a
dehumidifier can be used to maintain the humidity within an acceptable range.