NEC POWERMATE 5100 - SERVICE, Service Manual

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4-12 System Board

PS/2-style keyboard

Bi-directional Enhanced Parallel Port (EPP) and Enhanced
Capabilities Port (ECP) support for a parallel printer

Serial devices through two buffered 16C550 UART serial ports,
supporting up to 115.2 KB per second

Two USB devices

Speaker and microphone connectors (line out, microphone in).
The following table lists the major components on the system board.
System Board Components
Component Function
Celeron Processor (mounted in a
S.E.C. cartridge) 266-MHz Celeron processor
300-MHz Celeron processor
or
Pentium II Processor (mounted in a
S.E.C. cartridge) 233-MHz Pentoim II processor
266-MHz Pentium II processor
300-MHz Pentium II processor
333-MHz Pentium II processor
Intel 440EX AGPset:
82443BEX PCI/AGP controller
(PAC) Provides bus control signals, address paths, and data paths for
transfers between the processor’s host bus, PCI bus, AGP
controller, and system memory.
Features include processor interface control (32-bit addressing,
66-MHz host bus speed), an integrated DRAM controller
(synchronous DRAM, 64/72-bit path-to-memory, auto detection
of memory type) and an AGP interface (compliant with AGP
specification with data transfer rates up to 133 MHz), PCI bus
interface (compliant with PCI specification Revision 2.1), and
data buffering.
82371EB PCI ISA IDE Xcelerator
(PIIX4E) Functions as a PCI to ISA bridge; PCI IDE functionality; a USB
controller; integrated dual channel enhanced IDE interface with
support for Ultra DMA/33; enhanced DMA controller; interrupt
controller based on 82C59, with support for 15 interrupts; power
management logic (sleep/resume, remote wake on LAN, and
support for ACPI); real-time clock with 256-byte, battery-backed
CMOS static RAM (SRAM); 16-bit counters based on 82C54.
National Heceta LM80 Provides voltage, temperature, and security monitoring (NEC
MagicEye technology).