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Changing the Jumper Settings
The jumpers on the main system board control certain
functions and are preset at the factory to default positions;
however, you can use the information in the following tables to
change their settings, if necessary. (The jumpers listed in the
tables are the only ones you may need to change; others are for
service purposes only.)
Miscellaneous jumper settings
jumper Jumper
number setting
Function
JA
1-2*
Enables LPT (parallel port)
2-3
Disables LPT (parallel port)
JB**
1-2*
Enables HDC (lDE hard disk drive controler)
2-3
Disables HDC ODE hard disk drive controler)
JC
1- 2*
Enables COMA (serial port1)
2-3
Disables COMA (serial part 1)
JD
1-2*
Enables COMB (serial port 2)
2-3
Disables COMB (serial-port 2)
JE**
J4
1-2*
Enables HDC (lDE hard disk drive controller)
2-3
Dlsablss HDC (IDE hard disk drive controller)
1-2
Enables game port (J1)
2-3*
Disables game port (J1)
J5
1-2*
2-3
Assigns the parallel port as LPTl (378h-37Fh)
Assigns the parallel port as LPT2 (278h-27Fh)
J6
1-2*
2-3
Assigns serial port 1 as COM1 (3F8h-3FFh)
Assigns serial port 1 as COM3 (3E8h-3EFh)
J7
1-2*
2-3
Assigns serial port 2 as COM2 (2F8h-2FFh)
Assigns serlal port 2 as COM4 (2E8h-2EFh)
J8
J10
1-2*
2-3
On*
Off
1-2
Enables the diskette drive controlIer
Disables the diskette drive controller
Enables VGA interrupt
Disables VGA interrupt
J17***
Microprocessor installed runs at 33 MM or 66 MM or a
multiple of these (486SX/33. 486DX/33, 486DX2/66, DX4/100
and Pentium)
3-4
Microprocessor installed is a 486DX/50
1-2, 3-4
Microprocssor installed is a DX/40
5-6
Microprocessor installed at 25 MHz or 50 MHz or a
multIpIe of these (486SX/25, 486DX2/50. DX4/75. and SX2/50)
3-6
Installing
and Removing Options