Intel Above Board/PS configuration stason.org
has information on Intel Above Board/PS switch settings.
They switched the names of switch blocks.
I'll mirror it here:
__
+-----------------------------------------------------|
| *** *** *** *** *** *** ****** ********** |-+
| *b* *b* *b* *b* *b* *b* *SW1 * * SW2 * | | serial
| *a* *a* *a* *a* *a* *a* ****** ********** |-+
| *n* *n* *n* *n* *n* *n* |-+
| *k* *k* *k* *k* *k* *k* | |
| * * * * * * * * * * * * | | parallel
| *5* *4* *3* *2* *1* *0* | |
| * * * * * * * * * * * * | |
| *** *** *** *** *** *** |-+
+---------------------------+--------------------+----|
|____________________| |
bold - factory default setting
Parallel port
SW1-1
SW1-2
LPT1 (378h) off
on
LPT2 (278h)
on
off
disabled
off
off
Serial port
SW1-3
SW1-4
COM1 (3F8h) off
on
COM2 (2F8h)
on
off
disabled
off
off
Real-time clock
SW2-1
RTC enabled on
RTC disabled
off
Base memory backfill start address
SW2-2
SW2-3
256K off
on
512K
on
off
none
on
on
I/O port address
SW2-4
SW2-5
SW2-6
none
off
off
off
208h - 20Fh
off
off
on
218h - 21Fh
off
on
off
258h - 25Fh off
on
on
268h - 26Fh
on
off
off
2A8h - 2AFh
on
off
on
2B8h - 2BFh
on
on
off
2E8h - 2EFh
on
on
on
DRAM chip type
SW2-7
64K (4164)
off
256K (41256)
on
SW2-8 is factory configured. Don't change.