5
Removal and replacement
procedures: Tower (TWR)
Adherence to the procedures and precautions described in this chapter is essential for proper service.
After completing all necessary removal and replacement procedures, run the Diagnostics utility to verify
that all components operate properly.
NOTE:
Not all features listed in this guide are available on all computers.
Preparation for disassembly
See
Routine care, SATA drive guidelines, and disassembly preparation on page 28
for initial safety
procedures.
1.
Remove/disengage any security devices that prohibit opening the computer.
2.
Remove all removable media, such as compact discs or USB flash drives, from the computer.
3.
Turn off the computer properly through the operating system, then turn off any external devices.
4.
Disconnect the power cord from the power outlet and disconnect any external devices.
CAUTION:
Turn off the computer before disconnecting any cables.
Regardless of the power-on state, voltage is always present on the system board as long as the
system is plugged into an active AC outlet. In some systems the cooling fan is on even when the
computer is in the “Standby,” or “Suspend” modes. The power cord should always be
disconnected before servicing a unit.
5.
As applicable, lay the computer down on its side to achieve a safe working position.
NOTE:
During disassembly, label each cable as you remove it, noting its position and routing.
Keep all screws with the units removed.
CAUTION:
The screws used in the computer are of different thread sizes and lengths; using the
wrong screw in an application may damage the unit.
Preparation for disassembly
37
