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2.3.2 Processor frequency Selection (JP3)
JP3 is a 2x6-pin jumper block with Easy-jumper cap on it for you to select the processor’s working
speed easily.
400
450
500
RS0
RS1
Processor
ON
OFF
OFF
OFF
OFF
For Pentium
®
II 400 MHz
OFF
ON
OFF
OFF
OFF
For Pentium
®
II 450 MHz
OFF
OFF
ON
OFF
OFF
For Pentium
®
II 500 MHz
Note: This jumper is able to provide more powerful functions, which are reserved for technician’s
special testing purpose only. DO NOT use these functions unless you are an experienced user
and you are willing to take your risk.
2.3.3 Main memory (DIMM0--3)
The motherboard has four dual inline memory module (DIMM) sockets, which supports memory
size from 8 MB to 2 GB with SDRAM. The Synchronous DRAM (SDRAM) improves memory
performance through memory access that is synchronous with the memory clock. The Error
Checking and Correcting (ECC) memory improves system security by detecting and correcting
error bit when accessing memory.
The motherboard supports the following memory features:
JEDEC MO-161 compliant 168-pin DIMMs with gold-plated contacts
3.3 V memory module only
ECC logic detects multiple-bit errors and corrects single-bit errors (SDRAM)
Unbuffered SDRAM, Registered DIMM
16 / 64 Mbit DRAM technology
Symmetrical and asymmetrical DRAM addressing
Single-sided or double-sided DIMMs
Registered and Unbuffered DIMMs can NOT be installed on the same motherboard
Memory can be installed in DIMM sockets without any order restriction. The memory size, speed
can vary between sockets. The BIOS automatically detects memory type, size and speed.
Note 1. In order to reduce the loading, the total memory chip count installed on the system should
not exceed 72 unless the Registered DIMMs are used.
Note 2. The Serial Presence Detect (SPD) information is highly recommended on all 100 MHz
DIMMs for this motherboard. This function is implemented using an EEPROM component on the
memory module. The nonvolatile storage device contains data programmed by the DIMM
manufacturer that identifies the module type and various SDRAM organization and timing
parameters. A warning message will be prompted if any DIMMs installed on this motherboard has
no SPD EEPROM. In this case, the system might fail to be stable without correct timing
parameters.
