Joseph, I think is would be a safe bet that plugging the power cord into the
keyboard socket fried the motherboard and everything on it.  Your question
is "Can I salvage this 486".  If you could find a mobo for it, and
replacements for everything else that got fried you probably could.  The
time and cost would make this project not worth it.  I'd go look for a
refurbished newer version at a cost not much more than fixing the old 486
would cost. I've seen web sites advertising laptops (refurbished) with
P166's, PII 233's for as low as $399.00.  I don't know how good they are,
but at $399 you will have a more current machine, and still will spend less
than the cost of repairing the Acer 486 even assuming you could still get
parts for it.  Unlike your NEC/HP printer, you would not be throwing away a
good machine since the guts of the computer are already deceased.  You may
have fried your RAM and your CPU along with the mobo.  Have someone test
this stuff to make sure.  If you didn't fry it all, and the mobo still works
(I doubt it), go ahead and try to save it.

Dear Listers,
I would like to solicit opinion regarding the repairability of an Acer 486
Laptop which used a P/S 2 port for its external power connection.
Unfortunately the power cord was plugged into the keyboard socket. I know,
the motherboard is most likely fried, but I would like to know if there is a
probability for salvage.

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