NEC MT-2550-24874C, Руководство по обслуживанию

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B-4 System Board Settings
The following table summarizes the system board jumper settings.
Table B-1 System Board Jumper Settings
Function Jumper
J9C1 Configuration
Processsor Frequency A 2-3 (233 MHz) or 1-2 (266 MHz)
B 2-3 and 5-6 (233 MHz) or 1-2
and 4-5 (266 MHz)
C 2-3
Password Clear D 1-2 Password
clear/disabled
2-3 Password
enabled (default)
CMOS (NVRAM and
ESCD Clear) C 5-6 Keep (default)
4 - 5 Clear
BIOS Setup Access D 5-6 Access enabled
(default)
4-5 Access denied
Host Bus Frequency* C 2-3
BIOS Recovery A 5-6 Normal operation
(default)
4-5 Recover BIOS
*Jumper also sets the PCI and ISA bus frequencies
Changing System Board Jumper Settings
The following subsections describe how to verify or change system board jumper settings.
Processor/Bus Speed Jumpers
The system board must be configured for the frequency of the installed processor and the
corresponding host bus, PCI bus, and ISA bus frequencies. This jumper should be set
correctly at the factory for the system.
The following procedure explains how to locate and change the processor speed jumper
setting in the unlikely event that it is not set correctly at the factory.
WARNING:
The system power must be off
before changing a jumper setting.