NOTE: If you are using a different operating system, see the documentation of your operating system for shut-downinstructions.3. Disconnect your computer and all attached devices from their electrical outlets.4. Disconnect all attached network devices and peripherals, such as keyboard, mouse, and monitor from your computer.CAUTION: To disconnect a network cable, first unplug the cable from your computer and then unplug thecable from the network device.5. Remove any media card and optical disc from your computer, if applicable.Safety precautionsThe safety precautions chapter details the primary steps to be taken before performing any disassembly instructions.Observe the following safety precautions before you perform any installation or break/fix procedures involving disassembly orreassembly:● Turn off the system and all attached peripherals.● Disconnect the system and all attached peripherals from AC power.● Disconnect all network cables, telephone, and telecommunications lines from the system.● Use an ESD field service kit when working inside any to avoid electrostatic discharge (ESD) damage.● After removing any system component, carefully place the removed component on an anti-static mat.● Wear shoes with non-conductive rubber soles to reduce the chance of getting electrocuted.Standby powerDell products with standby power must be unplugged before you open the case. Systems that incorporate standby power areessentially powered while turned off. The internal power enables the system to be remotely turned on (wake on LAN) andsuspended into a sleep mode and has other advanced power management features.Unplugging, pressing and holding the power button for 15 seconds should discharge residual power in the system board.BondingBonding is a method for connecting two or more grounding conductors to the same electrical potential. This is done throughthe use of a field service electrostatic discharge (ESD) kit. When connecting a bonding wire, ensure that it is connected to baremetal and never to a painted or non-metal surface. The wrist strap should be secure and in full contact with your skin, andensure that you remove all jewelry such as watches, bracelets, or rings prior to bonding yourself and the equipment.Electrostatic discharge—ESD protectionESD is a major concern when you handle electronic components, especially sensitive components such as expansion cards,processors, memory DIMMs, and system boards. Very slight charges can damage circuits in ways that may not be obvious, suchas intermittent problems or a shortened product life span. As the industry pushes for lower power requirements and increaseddensity, ESD protection is an increasing concern.Due to the increased density of semiconductors used in recent Dell products, the sensitivity to static damage is now higher thanin previous Dell products. For this reason, some previously approved methods of handling parts are no longer applicable.Two recognized types of ESD damage are catastrophic and intermittent failures.● Catastrophic – Catastrophic failures represent approximately 20 percent of ESD-related failures. The damage causesan immediate and complete loss of device functionality. An example of catastrophic failure is a memory DIMM that hasreceived a static shock and immediately generates a "No POST/No Video" symptom with a beep code emitted for missing ornonfunctional memory.● Intermittent – Intermittent failures represent approximately 80 percent of ESD-related failures. The high rate ofintermittent failures means that most of the time when damage occurs, it is not immediately recognizable. The DIMMreceives a static shock, but the tracing is merely weakened and does not immediately produce outward symptoms related tothe damage. The weakened trace may take weeks or months to melt, and in the meantime may cause degradation of memoryintegrity, intermittent memory errors, etc.26 Working inside your computer