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R-01-01-080319
686BX
USER'S MANUAL
1. System power on by PS/2 Mouse: First, enable this function
in CMOS Setup, then you can power on the system by double
clicking the right or left button of your PS/2 Mouse.
2. System power on by Keyboard: If your ATX power supply
supports larger than 720 mA 5V Stand-By current, you can
power on your system by entering password from the
keyboard after setting the “Keyboard power on” password in
CMOS Setup.
3. Supports 3 steps ACPI LED.
4. Modem Ring-On. (COM B)
5. Wake-Up on LAN. (on J13)
6. Supports LDCM®
Pentium II Processor MAINBOARD
REV. 1.0 First Edition
Release Date 98.03.19
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686BX
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The author assumes no responsibility for any errors or omissions that may
appear in this document nor does it make a commitment to update the
information contained herein.
Third-party brands and names are the property of their respective owners.
March 19, 1998 Taipei, Taiwan
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Quick Installation Guide
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I. Quick Installation Guide :
CPU SPEED SETUP
The system bus speed is selectable between 66.6MHz and 100 MHz. The
user can select the system bus speed (JP6) and change the DIP SWITCH
(SW) selection to set up the CPU speed for 200 - 633MHz processor.
The CPU speed MUST match with the frequency RATIO. It will cause
system hanging up if the frequency RATIO is higher than that of CPU.
CLK RATIO SW 1 SW 2 SW 3 SW 4
X3
ON OFF ON ON
X3.5
OFF OFF ON ON
X4
ON ON OFF ON
X4.5
OFF ON OFF ON
X5
ON OFF OFF ON
X5.5
OFF OFF OFF ON
JP6
1-2 CLOSE : System Speed is set to 66 MHz
2-3 CLOSE : Reserved (For Future use only!)
1-2-3 OPEN : System Speed is set to 100MHz
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686BX
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I. Set system speed to 66MHz: JP6 pin 1-2 short will cause
system always run at 66 MHz FSB (Front Side Bus).
II. Set system speed to 100MHz: JP6 pin 1-2-3 open will cause
system always run at 100MHz FSB.
III. Function for future use: Please don’ t short this pins right now!
1. Pentium II 300 / 100MHz FSB
JP6 1
PIIX4
82443BX
ON
4 3 2 1
JP6
JP6
3 2 1
JP6
3 2 1
JP6
3 2 1
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Quick Installation Guide
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2. Pentium II 350 / 100MHz FSB
3. Pentium II 400 / 100MHz FSB
4. Pentium II 450 / 100MHz FSB
5. Pentium II 233 MHz / 66MHz FSB
SW
ON
JP6
JP6
JP6
JP6
3 2 1
3 2 1
3 2 1
3 2 1