Dell OptiPlex NX User Manual

Also see for OptiPlex N: Troubleshooting guide Service manual

2-2 Dell OptiPlex N and OptiPlex NX Systems User’s GuideCleaning the Computer, Monitor, andKeyboard Exteriors1. Turn off the computer, the monitor, and anyattached peripherals, and disconnect them fromtheir power sources.2. Use a vacuum cleaner to remove any dust fromthe slots and holes on the computer and betweenthe keys on the keyboard.3. Moisten a soft cleaning cloth with a dishwashingdetergent solution, and use the cloth to wipe thecomputer cover, the keyboard, and the exterior ofthe monitor, including the screen.Do not soak the cloth in the solution; you must notlet the solution drip inside the computer or the key-board. If you get moisture into any of the computercomponents, contact your network administratorimmediately.Minimizing EnvironmentalHazardsThis section discusses various environmental factors thatcan adversely affect system performance and longevity.TemperatureTemperature extremes can cause a variety of problems,including premature aging and failure of chips andmechanical failure of devices. Extreme temperature fluc-tuations can cause chips to become loose in their socketsand can cause expansion and contraction of disk driveplatters, resulting in read or write data errors.There are several guidelines you can follow to minimizethe negative effects of temperature on systemperformance.For optimum system performance, follow theseguidelines:• Operate the system in an environment no colder than10° Celsius (C) (50° Fahrenheit [F]) or hotter than35°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 onthe front of the computer.Do not place the system within a closed-in wall unitor on top of cloth material, which can act as insula-tion. Do not place it where it will receive directsunlight. Do not place it next to a heat source of anykind, including heating vents during the winter.• Clean the system at regular intervals to avoid anybuildup of dust and debris, which can cause a systemto overheat.• If the system has been exposed to abnormally coldtemperatures, allow a 15-minute warm-up periodbefore it is turned on and starts attempting to readfrom or write to the hard-disk drive.• If you notice intermittent system failures, ask yournetwork administrator or a service technician toreseat any socketed chips, which might have becomeloose because of temperature fluctuations.HumidityHigh-humidity conditions can cause moisture to collectin the computer. This moisture can cause corrosion ofinternal components and degradation of properties suchas electrical resistance, thermal conductivity, physicalstrength, and size. Extreme moisture buildup inside thecomputer can result in electrical shorts, which can causeserious damage to the computer.Each Dell system is rated to operate at 20 percent to80 percent relative humidity, with a humidity gradationof 10 percent per hour. In storage, a Dell system canwithstand from 5 percent to 95 percent relative humidity.Buildings in which climate is controlled by air-conditioning in the warmer months and by heat duringthe colder months usually maintain an acceptable level ofhumidity for computer equipment. However, if a systemis located in an unusually humid location, use a dehumid-ifier to maintain the humidity within an acceptable range.AltitudeOperating a system at high altitude (low pressure)reduces the efficiency of forced and convection coolingand can result in electrical problems related to arcing and