Fixing a 386SX laptop

Chuck Guzis cclist at
Fri Oct 9 17:10:37 CDT 2009

On 10 Oct 2009 at 0:41, Alexandru Lovin wrote:

> Trouble is, I can't afford an international call to hear them say yes
> or no. Beside that, I really really really want someone to look into
> the machine and tell me if a custom RAM card can be made. The thing
> comes with 2 MB onboard (4 chips, apparently 4x512 KB) and it has a
> custom RAM upgrade card...which of course, can't be found anywhere on
> the whole Internet.

You didn't say where in the world you were located.  I'm sure that 
there must be someone close enough to you.

> Now, the laptop also has a custom connector for a 2400bps modem that
> it could host. Being a 386SX, it is most definitely 8-bit ISA or
> 16-bit ISA (but really nonstandard). I think it has 25 pins or so (not
> sure, quoting from memory). Were there any other buses used in the
> 286-386SX generations except ISA? As far as I know, PCI can only be
> implemented starting with a 386 DX so it's definitely not PCI.

I'm sure it's nothing as exotic as PCI for a 386SX laptop.  It could 
well be a version of ISA, but some devices used their own bus 
implementation, so it's difficult to say.

> I refuse to believe that there aren't any people left in this world
> able to design and manufacture a custom PCB. One for the memory
> expansion (and not necessarily with 2 MB on it, it can have more - the
> 386SX I heard can access up to 16 MB, just like the 286, while the
> leap to 4 GB was achieved with the 386DX) and one for something else.

The question is more of "who would want to design a board for a 
little-known vintage laptop?" Given sufficient monetary impetus, you 
could certainly find someone to do it, but otherwise, why would 
anyone want to do it?

I think it's a better use of your time to enjoy the thing for what it 
is, not what it was never intended to be.


More information about the cctech mailing list