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.
I
Miscellaneous jumper settings
Jumper
Jumper
lumber
setting
Function
J A
1-2 *
Enables LPT (parallel port)
2-3
Disables LPT (parallel port)
JB **
1-2 *
Enables HDC (IDE hard disk drive controller)
2-3
Disables HDC (IDE hard disk drive controller)
J C
1-2*
Enables COMA (serial port 1)
2-3
Disables COMA (serial port 1)
1-2 *
Enables COMB (serial port 2)
2-3
Disables COMB (serial port 2)
JE **
1-2*
Enables HDC (IDE hard disk drive controller)
2-3
Disables HDC (IDE hard disk drive controller)
J4
1-2
Enablesgame port (J1)
2-3 *
Disables game port (J1)
J5
1-2*
Assigns the parallel port as LPT1 (378h-37Fh)
2-3
Assigns the parallel port as LPT2 (278h-27Fh)
J6
1-2*
Assigns serial port 1 as COM1 (3F8h-3FFh)
2-3
Assigns serial port 1 as COM3 (3E8h-3EFh)
J7
1-2 *
Assigns serial port 2 as COM2 (2F8h-2FFh)
2-3
Assigns serial port 2 as COM4 (2E8h-2EFh)
J8
1-2 *
Enablesthe diskette drive controller
2-3
Disables the diskette drive controller
J10
On *
Enable VGA interrupt
Off
Disable VGA interrupt
J17 ***
1-2
Microprocessor installed runs at 33 MHz or 66 MHz or a
multiple of these (486SX/33, 486DX/33, 486DX2/66, DX4/100,
or Pentium)
3-4
Microprocessor installed is a 486DX/50
1-2,3-4
Microprocessor installed is a DX/40
5-6
Microprocessor installed runs at 25 MHz or 50 MHz or a
multiple of these (486SX/25, 486DX2/50, DX4/75, or SX2/50)
3 - 6
Installing and Removing Options