Compaq 7RPK11 7000T, Руководство по техническому обслуживанию и ремонту

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United States
Compaq Presario Internet PC 7000 Series Computers
REMOVAL AND REPLACEMENT PROCEDURES
PRODUCT DESCRIPTION TROUBLESHOOTING ILLUSTRATED PARTS CATALOG
REMOVAL AND REPLACEMENT PROCEDURES
JUMPER AND SWITCH INFORMATION SPECIFICATIONS
ELECTROSTATIC
DISCHARGE
SERVICE
CONSIDERATIONS
PREPARATION FOR
DISASSEMBLY
SERIAL NUMBER
SIDE ACCESS PANEL
GRAPHICS CARD
EXPANSION CARD
(Modem or Network
Card)
SOUND CARD
1394 CARD
MEMORY MODULE
HARD DRIVE
DISK DRIVE
REMOVING THE TOP
DOOR
REMOVING THE CD
STORAGE DOOR
(Lower Front Panel -
Open the CD Storage
Door)
OPTICAL AND MASS
Electrostatic Discharge
A sudden discharge of static electricity from a finger or a 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 (ESD) may not be
affected at all and will work perfectly throughout a normal cycle. Or it may function
normally for a while, then degrade in the internal layers, reducing its life expectancy.
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.
Generating Static
The table below shows the different amounts of static electricity generated by different
activities.
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 400V
Removing DIPS from
plastic tubes
2,000 V 700 V 400 V
Removing DIPS from
vinyl trays
11,500 V 4,000 V 2,000 V