compaq presario 900 series User Manual

							3–14Maintenance and Service Guide
Illustrated Parts Catalog
3.6 Miscellaneous
Ta b l e  3 - 5
Spare Parts: Miscellaneous (not illustrated)
DescriptionSpare Part 
Number
Logo Kit285547-001
Screw Kit, includes the following screws (Refer to Appendix C, 
“Screw Listing,” for more information on screw specifications 
and usage.)285542-001
■Torx T8 Metric 2.5 × 5.0
■Torx T8 Metric 2.5 × 8.0
■Torx T8 Metric 2.5 × 9.0
■Torx T8 Metric 2.5 × 14.0
shoulder screw
■Phillips Metric 3.0 × 3.0
■Phillips Metric 2.5 × 4.0
■Phillips Metric 2.0 × 4.5
AC adapter, 90 W, 3 wire, slim line286755-001
Power cords, 3 wire
Danish
International
Italian170513-081
170513-002
170513-061Swiss
U.K. English
U.S. English170513-115
170513-031
170513-001
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							Maintenance and Service Guide4–1
4
Removal and Replacement
Preliminaries
This chapter provides essential information for proper and safe 
removal and replacement service.
4.1 Tools Required
You will need the following tools to complete the removal and 
replacement procedures:
■Magnetic screwdriver
■Phillips P0 screwdriver
■Torx T8 screwdriver
■Tool kit (includes connector removal tool, loopback plugs, 
and case utility tool)
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							4–2Maintenance and Service Guide
Removal and Replacement Preliminaries
4.2 Service Considerations
The following sections include some of the considerations that 
you should keep in mind during disassembly and assembly 
procedures.
✎As you remove each subassembly from the computer, place the 
subassembly (and all accompanying screws) away from the work 
area to prevent damage.
Plastic Parts
Using excessive force during disassembly and reassembly can 
damage plastic parts. Use care when handling the plastic parts. 
Apply pressure only at the points designated in the maintenance 
instructions.
Cables and Connectors
Cables must be handled with extreme care to avoid damage. 
Apply only the tension required to unseat or seat the cables 
during removal and insertion. Handle cables by the connector 
whenever possible. In all cases, avoid bending, twisting, or 
tearing cables. Ensure that cables are routed in such a way that 
they cannot be caught or snagged by parts being removed or 
replaced. Handle flex cables with extreme care; these cables tear 
easily.
ÄCAUTION: When servicing the computer, ensure that cables are 
placed in their proper locations during the reassembly process. 
Improper cable placement can damage the computer.
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							Removal and Replacement Preliminaries
Maintenance and Service Guide4–3
4.3 Preventing Damage to 
Removable Drives
Removable drives are fragile components that must be handled 
with care. To prevent damage to the computer, damage to a 
removable drive, or loss of information, observe the following 
precautions:
■Before removing or inserting a hard drive, shut down the 
computer. If you are unsure whether the computer is off or in 
Hibernation, turn the computer on, then shut it down.
■Before removing a diskette drive or optical drive, ensure that 
a diskette or disc is not in the drive. Ensure that the optical 
drive tray is closed.
■Before handling a drive, ensure that you are discharged of 
static electricity. While handling a drive, avoid touching the 
connector.
■Handle drives on surfaces that have at least one inch of 
shock-proof foam.
■Avoid dropping drives from any height onto any surface.
■After removing a hard drive, CD-ROM drive, or a diskette 
drive, place it in a static-proof bag.
■Avoid exposing a hard drive to products that have magnetic 
fields, such as monitors or speakers.
■Avoid exposing a drive to temperature extremes or to liquids.
■If a drive must be mailed, place the drive in a bubble-pack 
mailer or other suitable form of protective packaging and 
label the package “Fragile: Handle With Care.”
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							4–4Maintenance and Service Guide
Removal and Replacement Preliminaries
4.4 Preventing Electrostatic Damage
Many electronic components are sensitive to electrostatic 
discharge (ESD). Circuitry design and structure determine the 
degree of sensitivity. Networks built into many integrated circuits 
provide some protection, but in many cases the discharge contains 
enough power to alter device parameters or melt silicon junctions.
A sudden discharge of static electricity from a finger or other 
conductor can destroy static-sensitive devices or microcircuitry. 
Often the spark is neither felt nor heard, but damage occurs.
An electronic device exposed to electrostatic discharge may not 
be affected at all and can work perfectly throughout a normal 
cycle. Or the device may function normally for a while, then 
degrade in the internal layers, reducing its life expectancy.
4.5 Packaging and Transporting 
Precautions
Use the following grounding precautions when packaging and 
transporting equipment:
■To avoid hand contact, transport products in static-safe 
containers, such as tubes, bags, or boxes.
■Protect all electrostatic-sensitive parts and assemblies with 
conductive or approved containers or packaging.
■Keep electrostatic-sensitive parts in their containers until the 
parts arrive at static-free workstations.
■Place items on a grounded surface before removing items 
from their containers.
■Always be properly grounded when touching a sensitive 
component or assembly.
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							Removal and Replacement Preliminaries
Maintenance and Service Guide4–5
■Store reusable electrostatic-sensitive parts from assemblies in 
protective packaging or nonconductive foam.
■Use transporters and conveyers made of antistatic belts and 
roller bushings. Ensure that mechanized equipment used for 
moving materials is wired to ground and that proper materials 
are selected to avoid static charging. When grounding is not 
possible, use an ionizer to dissipate electric charges.
4.6 Workstation Precautions
Use the following grounding precautions at workstations:
■Cover the workstation with approved static-dissipative 
material (refer to Table 4-2).
■Use a wrist strap connected to a properly grounded work 
surface and use properly grounded tools and equipment.
■Use conductive field service tools, such as cutters, 
screwdrivers, and vacuums.
■When using fixtures that must directly contact dissipative 
surfaces, only use fixtures made of static-safe materials.
■Keep the work area free of nonconductive materials, such as 
ordinary plastic assembly aids and Styrofoam.
■Handle electrostatic-sensitive components, parts, and 
assemblies by the case or PCM laminate. Handle these items 
only at static-free workstations.
■Avoid contact with pins, leads, or circuitry.
■Turn off power and input signals before inserting or removing 
connectors or test equipment.
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							4–6Maintenance and Service Guide
Removal and Replacement Preliminaries
4.7 Grounding Equipment and Methods
Grounding equipment must include either a wrist strap or a foot 
strap at a grounded workstation.
■When seated, wear a wrist strap connected to a grounded 
system. Wrist straps are flexible straps with a minimum of 
one megohm ±10% resistance in the ground cords. To 
provide proper ground, wear a strap snugly against the skin 
at all times. On grounded mats with banana-plug connectors, 
connect a wrist strap with alligator clips.
■When standing, use foot straps and a grounded floor mat. 
Foot straps (heel, toe, or boot straps) can be used at standing 
workstations and are compatible with most types of shoes 
or boots. On conductive floors or dissipative floor mats, use 
foot straps on both feet with a minimum of one-megohm 
resistance between the operator and ground. To be effective, 
the conductive strips must be worn in contact with the skin.
Other grounding equipment recommended for use in preventing 
electrostatic damage includes:
■Antistatic tape
■Antistatic smocks, aprons, and sleeve protectors
■Conductive bins and other assembly or soldering aids
■Nonconductive foam
■Conductive tabletop workstations with ground cords of 
one-megohm resistance
■Static-dissipative tables or floor mats with hard ties to 
the ground
■Field service kits
■Static awareness labels
■Material-handling packages
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							Removal and Replacement Preliminaries
Maintenance and Service Guide4–7
■Nonconductive plastic bags, tubes, or boxes
■Metal tote boxes
■Electrostatic voltage levels and protective materials
Table 4-1 shows how humidity affects the electrostatic voltage 
levels generated by different activities.
Table 4-2 lists the shielding protection provided by antistatic bags 
and floor mats.
Ta b l e  4 - 1
Typical Electrostatic Voltage Levels
Relative Humidity
Event 10% 40% 55%
Walking across carpet 35,000 V 15,000 V 7,500 V
Walking across vinyl floor 12,000 V  5,000 V 3,000 V
Motions of bench worker 6,000 V 800 V 400 V
Removing DIPS from plastic tube 2,000 V 700 V 400 V
Removing DIPS from vinyl tray 11,500 V 4,000 V 2,000 V
Removing DIPS from Styrofoam 14,500 V 5,000 V 3,500 V
Removing bubble pack from PCB 26,500 V 20,000 V 7,000 V
Packing PCBs in foam-lined box 21,000 V 11,000 V 5,000 V
✎A product can be degraded by as little as 700 V.
Table 4-2
Static-Shielding Materials
Material Use Voltage Protection Level
Antistatic plastic Bags 1,500 V
Carbon-loaded plastic Floor mats 7,500 V
Metallized laminate Floor mats 5,000 V
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							Maintenance and Service Guide5–1
5
Removal and Replacement
Procedures
This chapter provides removal and replacement procedures.
There are 57 screws, in seven different sizes, that must be 
removed and replaced when servicing the computer. Make 
special note of each screw size and location during removal and 
replacement. 
Refer to Appendix C, “Screw Listing,” for detailed information 
on screw sizes, locations, and usage.
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							5–2Maintenance and Service Guide
Removal and Replacement Procedures
5.1 Serial Number
Report the computer serial number to Compaq when requesting 
information or ordering spare parts. The serial number is located 
on the bottom of the computer as indicated in Figure 5-1.
Figure 5-1. Serial Number Location
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