Dell Inspiron 3000 Reference and Troubleshooting Guide - Page 4

computer, wait 5 seconds after turning off the computer before removing the memory module or disconnecting the device to help avoid possible damage to the system board. • Before you clean your computer, turn it off, unplug it from its power source, and remove the battery. • Clean your computer with a soft cloth dampened with water rather than with liquid or aerosol cleaners. Clean the display with a soft, clean cloth and commercial window cleaner that does not contain wax or abrasives. Apply the cleaner to the cloth; then stroke the cloth across the display in one direction, moving from the top of the display to the bottom. If the display contains grease or some other contaminant, use isopropyl alcohol instead of commercial window cleaner. • If your computer gets wet or is damaged, follow the procedures described in Chapter 3, "Troubleshooting Your Computer." If, after following these procedures, you confirm that your computer is not operating properly, contact Dell Computer Corporation. (See Chapter 5, "Getting Help," for the appropriate telephone number.) Ergonomic Computing Habits WARNING: Improper or prolonged keyboard use may result in injury. For comfort and efficiency, observe the following ergonomic guidelines when setting up and using your computer: • Position your computer directly in front of you as you work. • Adjust the tilt of the computer's display, its contrast and/or brightness settings, and the lighting around you (such as overhead lights, desk lamps, and the curtains or blinds on nearby windows) to minimize reflections and glare on the display. • When using an external monitor with your computer, set the monitor at a comfortable viewing distance (usually 510 to 610 millimeters [20 to 24 inches] from your eyes). Make sure the monitor screen is at eye level or slightly lower when you are sitting in front of the monitor. • Use a chair that provides good lower-back support. • Keep your forearms horizontal with your wrists in a neutral, comfortable position while using the keyboard, trackball, touch pad, or external mouse. • Always use the palmrest with the keyboard, touch pad, or trackball. Leave space to rest your hands when using an external mouse. • Let your upper arms hang naturally at your sides. • Sit erect with your feet resting on the floor and your thighs level. • When sitting, make sure the weight of your legs is on your feet and not on the front of your chair seat. Adjust your chair's height or use a footrest, if necessary, to maintain proper posture. • Vary your work activities. Try to organize your work so that you do not have to type for extended periods of time. When you stop typing, try to do things that use both hands. When Removing or Installing Memory Modules Before removing or installing memory modules, perform the following steps in the sequence indicated. CAUTION: The only time you should ever access the inside of your computer is when you are installing memory modules. Wait 5 seconds after turning off the computer before disconnecting a peripheral device or removing a memory module to help prevent possible damage to the system board. vi