NEC POWERMATE ES 5200 - SERVICE, Руководство по обслуживанию

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4-10 System Board
Pentium III Processor
The Pentium III processor has an internal clock speed of 450 or 500 MHz.
The processor features an optimized 64-bit memory interface and 512 KB of
secondary write-back cache. The processor utilizes the P6 Microarchitecture,
and incorporates 70 new instructions. It runs on the 100-MHz system bus and
incorporates the Intel 440BX chipset.
The Pentium III is geared for latest industry computing needs, including
advanced 3D effects, animation, imaging, video, and speech recognition.
System BIOS
The ISA- and PCI-compatible BIOS is contained in a flash memory device on
the system board. The BIOS provides the Power-On Self-Test (POST), the
system Setup program, a PCI and IDE auto-configuration utility, and BIOS
recovery code.
The system BIOS is always shadowed. Shadowing allows any BIOS routine to
be executed from fast 32-bit DRAM on the system board, instead of from the
slower 8-bit flash device.
NEC’s Flash ROM allows fast, economical BIOS upgrades. The Flash ROM is a
reprogrammable EPROM containing both the system and video BIOS. Using
the Flash ROM to change the ROM BIOS provides the following advantages:
„
the BIOS upgrade is performed quickly and easily
„
the expense of replacing ROM BIOS chips is eliminated, so system
maintenance costs are reduced
„
there is less chance of inadvertently damaging the system board than
when physically replacing ROMs
„
new technology can be incorporated while maintaining corporate
standards
„
network administrators can exercise company-wide control of BIOS
revisions.
The BIOS programs execute the Power-On Self-Test, initialize processor
controllers, and interact with the display, diskette drive, hard drives,
communication devices, and peripherals. The system BIOS also contains the
Setup utility. The POST copies the ROM BIOS into RAM (shadowing) for
maximum performance.
The Flash ROM allows the system and video BIOS to be upgraded with the
BIOS Update utility, without having to physically remove the ROM (see
Section 2 for further information on the BIOS Update utility). The Flash ROM
supports the reprogramming of the system BIOS and the video BIOS.