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4-10
Disassembly and Reassembly
Modifying the System Board
The following sections provide procedures for upgrading and configuring the
system board in your system. Topics covered include:
!
Replacing the real-time clock battery
!
Removing and installing a processor
!
Installing or removing DIMMs.
!
CAUTION
Electrostatic discharge (ESD) can damage add-in boards
and other components; place them on an antistatic surface.
Modify the system board only at an ESD workstation.
Otherwise, wear an antistatic wrist strap attached to chassis
ground.
Replacing the Real-time Clock Battery
You may need to replace the real-time clock (RTC) battery because of its life
span. The battery powers the clock in the absence of power. When the battery
starts to weaken, it loses voltage, and the system settings stored in CMOS RAM
(for example, the date and time) may be wrong.
The 3V battery (Vendor Part #CR2032) is a commodity part available through
many vendors. It is located on your system board (See Figure 4-5). Notice the
plus (+) sign on the battery. This sign will assist you in correctly positioning the
battery on the system board. Contact your sales representative or dealer for a list
of approved devices.
!
CAUTION
Danger of explosion if battery is incorrectly replaced.
Replace only with same or equivalent type recommended by
manufacturer. Dispose of lithium batteries as required by
local ordinance or as normal waste if no local ordinance
exists. Do not expose the component to excessive heat or
fire. Keep all batteries away from children
!
CAUTION
Observe static precautions. Use an antistatic wrist strap.
Summary of Contents for Express 5800/120Lg
Page 1: ... S e r v i c e G u i d e EXPRESS5800 120Lg ...
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Page 73: ...Disassembly and Reassembly 4 7 Figure 4 2 Installing the Left Hand Side Access Panel ...
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Page 161: ...6 Illustrated Parts Breakdown Exploded View Field Replaceable Units ...
Page 168: ......
Page 169: ...A Specifications System Specifications ...
Page 179: ...C IRQ and I O Port Addresses Interrupt Requests PIRQ and PCI Device ...
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