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 the
cable from the network device.
5. Remove any media card and optical disc from your computer, if applicable.
Safety precautions
The safety precautions section 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 or
reassembly:
● Turn off the computer and all attached peripherals.
● Disconnect the computer from AC power.
● Disconnect all network cables and peripherals from the computer.
● Use an ESD field service kit when working inside any to avoid electrostatic discharge (ESD) damage.
● After removing a computer 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.
● Unplugging, pressing, and holding the power button for 15 seconds should discharge residual power in the system board.
Standby power
Dell products with standby power must be unplugged before you open the case. Systems equipped with standby power are
powered while turned off. The internal power enables the computer to be remotely turned on (Wake-on-LAN) and suspended
into a sleep mode and has other advanced power management features.
Bonding
Bonding is a method for connecting two or more grounding conductors to the same electrical potential. This is done by using
a field service electrostatic discharge (ESD) kit. When connecting a bonding wire, ensure that it is connected to bare metal
and never to a painted or nonmetal surface. Ensure that the wrist strap is secure and in full contact with your skin. Remove all
jewelry such as watches, bracelets, or rings before to grounding yourself and the equipment.
Electrostatic discharge—ESD protection
ESD is a major concern when you handle electronic components, especially sensitive components such as expansion cards,
processors, memory modules, and system boards. A slight charge can damage circuits in ways that may not be obvious, such
as intermittent problems or a shortened product life span. As the industry pushes for lower power requirements and increased
density, 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 than
in 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 causes
an immediate and complete loss of device functionality. An example of catastrophic failure is a memory module that has
received a static shock and immediately generates a "No POST/No Video" symptom with a beep code that is emitted for
missing or non-functional memory.
● Intermittent – Intermittent failures represent approximately 80 percent of ESD-related failures. The high rate of
intermittent failures means that most of the time when damage occurs, it is not immediately recognizable. The memory
module receives a static shock, but the tracing is merely weakened and does not immediately produce outward symptoms
that are related to the damage. The weakened trace may take weeks or months to melt, and in the meantime may cause
degradation of memory integrity, intermittent memory errors, and so on.
Intermittent failures also called latent or "walking wounded" are difficult to detect and troubleshoot.
Perform the following steps to prevent ESD damage:
Working inside your computer
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