Dell OptiPlex GXi Reference and Installation Guide (.pdf) - Page 5

Safety Instructions When Using Your Computer System As you use your computer system, observe the following safety guidelines: • To help avoid damaging your computer, be sure the voltage selection switch on the power supply is set to match the alternating current (AC) power available at your location: - 115 volts (V)/60 hertz (Hz) in most of North and South America and some Far Eastern countries such as Japan, South Korea, and Taiwan - 230 V/50 Hz in most of Europe, the Middle East, and the Far East Also be sure your monitor and attached peripherals are electrically rated to operate with the AC power available in your location. • To help prevent electric shock, plug the computer and peripheral power cables into properly grounded power sources. These cables are equipped with 3-prong plugs to ensure proper grounding. Do not use adapter plugs or remove the grounding prong from a cable. If you must use an extension cable, use a 3-wire cable with properly grounded plugs. • To help protect your computer system from sudden, transient increases and decreases in electrical power, use a surge suppressor, line conditioner, or uninterruptible power supply. • Be sure nothing rests on your computer system's cables and that the cables are not located where they can be stepped on or tripped over. • Do not spill food or liquids on your computer. If the computer gets wet, consult your Diagnostics and Troubleshooting Guide. • Do not push any objects into the openings of your computer. Doing so can cause fire or electric shock by shorting out interior components. • Keep your computer away from radiators and heat sources. Also, do not block cooling vents. Avoid placing loose papers underneath your computer; do not place your computer in a closed-in wall unit or on a bed, sofa, or rug. Ergonomic Computing Habits WARNING: Improper or prolonged keyboard use may result in injury. For maximum comfort and efficiency, observe the following ergonomic guidelines when setting up and using your computer system: • Position your system so that the monitor and key- board are directly in front of you as you work. Special shelves are available (from Dell and other sources) to help you correctly position your keyboard. • 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. • Adjust the tilt of the monitor, its contrast and bright- ness 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 monitor screen. • Use a chair that provides good lower back support. v