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Table 1-8. Functional Structure Description
Bootup | CPU module | Main processor (MMO) |
| Motherboard | Primary system circuitry, system BIOS |
| Hard disk drive | First source of |
| Floppy drive | Second source of |
Processor | CPU module | Main processor, numeric data processor, L1 and L2 cache |
| Motherboard | Primary system circuitry |
Memory | Motherboard | Video RAM (XE4500) |
| SDRAM module | Changeable SDRAM (2 slots), video RAM (XE4100) |
Power | Battery | Power storage |
| Motherboard | AC adapter socket, reset button, lid switch, power supply, power |
| Switchboard PCA | control circuitry |
| Power button | |
| AC adapter | |
Display | Motherboard | Graphics controller, video RAM |
| SDRAM module | Display output, backlight, power converter for backlight |
| Display assembly |
|
Hard disk | Motherboard | Hard disk controller |
| Hard disk drive | Hard disk mechanism |
Floppy drive | Motherboard | I/O controller, floppy connector |
| Floppy drive | Floppy drive mechanism |
Keyboard | Motherboard | Keyboard BIOS, keyboard controller |
| Switchboard PCA | Power switch, |
| Keyboard | Key switches |
PS/2 | Motherboard | Keyboard circuitry, keyboard controller, keyboard BIOS |
TouchPad | Top case | Touch pad sensor, Select buttons, controller (PS/2 output) |
Audio | Motherboard | Audio controller, audio decoder, speaker amplifier, microphone, |
|
| external |
| Speaker assembly | audio jacks, headphone amplifier, |
|
| Speakers |
Status | Motherboard | LED circuitry, keyboard controller |
| Switchboard PCA | Keyboard LEDs |
| Top case | Main status LEDs |
Serial | Motherboard | I/O controller, serial connector |
|
|
|
Parallel | Motherboard | I/O controller, parallel connector |
|
|
|
Infrared | Motherboard | I/O controller |
| IR PCA | Infrared transmitter/receiver |
PS/2 port | Motherboard | PS/2 connector, keyboard controller |
USB | Motherboard | Bus controller (South Bridge), USB connector |
Motherboard | I/O controller, | |
|
|
|
Port Replicator | Motherboard | Port replicator logic, port replicator connector (certain models) |
|
|
|
PCMCIA | Motherboard | PCMCIA controller |
| PCMCIA socket | PCMCIA connector |
Wireless LAN | Mini PCI | I/O controller, radio, radio frequency circuitry |
(certain | Antenna PCAs | Transmit/receive antennas |
models only) | IR PCA | On/off switch, indicator light |
LAN | Motherboard | LAN circuitry, bus controller, LAN connector |
Modem | Motherboard | Modem circuitry (select models), modem connector |
Service Manual |