There are a lot more than 8 possible settings for the dip switch, since more
than one may be wrong.  Assume the board is set to expand a 256k machine.
It is also possible to add the memory at 640, 1024, 2048, 3072, and 4096.
It is best to use the memory at 1024 if you can figure out the switches.  That
leaves a hole between 640 and 1024, but it lets you use it there for extended
memory or for smartdrive disk caching. I used it years ago for lotus 123
extended memory for larger spreadsheets.  You will need programs meant
to run on 286's to take advantage of the extra memory since the DOS
operating system never supported the 286's memory addressing
scheme, although UNIX systems could.  Smartdrive comes with dos 6.22
and lotus included a memory extender, but most programs did not.  I did have
a copy of Rational's dos extender for 286's, similar to the one that powered
Spear of Destiny, but where you would find such a thing now is anyone's guess.
It ran an imaging program that came with my faxboard.

Having said all that, if you do get it working I would use it for smartdrive.  The cache
really improves 286 performance.  You can use IDE drives in a 286 with the oldest
BIOS as long as the drive doesn't compain about WPcomp and landing zone, since
you may not be able to configure that.  Just choose a BIOS disk table entry that
comes closest to your IDE drive size without going over.  If your BIOS does not
include a user entry, your probably stuck at a pretty small size, since most
table entries are below 80 meg, but I have seen some that go up to 350 meg.

My first build was converting an 512kb IBM AT running at 6 mhz into a
10mhz 286 with 1 meg on the motherboard.  I eventually tweaked it up to 5 meg
and was going to try UNIX when the 486's came out.  I still own that first 486,
although nothing is original other than the case and keyboard (yes, I have immersed
the keyboard in water to clean it).

Rather than scout for dos programs I would scout for a really cheap 386 or 486
motherboard with cpu and memory installed.  8 megs on a 486 SX would be
almost free.  That would allow you to run just about any windows 3.1 software,
and there are many good titles still out there second-hand.  Let the kids help.
Tom Turak

----------
From:   Kenneth Alan Boyd Ramsay
Sent:   Wednesday, April 28, 1999 4:01 AM

That "double" card sounds like a memory expansion card.  I have an old Intel
"Aboveboard" at the shop, which _might_ be like it.  Check all those 54
socketed chips.  Each chip should have a code like "XXxxx64x-20", and each
row of 9 should all be from the same manufacturer.  "XX" is a clue to the
manufacturer, if it does not have a recognizable logo.  "xxx64x" indicates
64K. Being in groups if 9 (6x9=54) indicates 8 bits-per-byte plus parity.
"-20" indicates 200 nanosecond response time. That would give you 384 K,
with 640 K on the motherboard, for a total of 1 Meg RAM.

Unfortunately, there is not much advantage to be gained by the extra 384 K,
especially as it will be operating at the ISA bus frequency, and not as
fast as the memory on the motherboard.

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