12 Before You BeginSafety InstructionsUse the following safety guidelines to protect your computer from potentialdamage and ensure your personal safety.WARNING: Before working inside your computer, read the safety informationthat shipped with your computer. For additional safety best practices information,see the Regulatory Compliance Homepage at dell.com/regulatory_compliance.WARNING: Disconnect all power sources before opening the computer cover orpanels. After you finish working inside the computer, replace all covers, panels,and screws before connecting to the power source.CAUTION: To avoid damaging the computer, ensure that the work surface is flatand clean.CAUTION: To avoid damaging the components and cards, handle them by theiredges and avoid touching pins and contacts.CAUTION: Only a certified service technician is authorized to remove thecomputer cover and access any of the components inside the computer. See thesafety instructions for complete information about safety precautions, workinginside your computer, and protecting against electrostatic discharge.CAUTION: Before touching anything inside your computer, ground yourself bytouching an unpainted metal surface, such as the metal at the back of thecomputer. While you work, periodically touch an unpainted metal surface todissipate static electricity, which could harm internal components.CAUTION: When you disconnect a cable, pull on its connector or on its pull-tab,not on the cable itself. Some cables have connectors with locking tabs orthumb-screws that you must disengage before disconnecting the cable. Whendisconnecting cables, keep them evenly aligned to avoid bending any connectorpins. When connecting cables, ensure that the connectors and ports are correctlyoriented and aligned.CAUTION: To disconnect a network cable, first unplug the cable from yourcomputer and then unplug the cable from the network device.Recommended ToolsThe procedures in this document may require the following tools:• Phillips screwdriver• Plastic scribe