It's probably just dual ps/2 on these older laptops, one for the keyboard and one for the mouse

Most probably this is the case.

I've been working a scratch build case with a very small footprint, albeit for a totally different purpose, so I've done some research and testing on compacting a retro system down. I'm not in the laptop scene at all, but here's something I found to keep in mind while you shop/plan:

Obviously whichever 3dfx card you pick will require some sort of riser cable to fit in the laptop shell. None of the AGP or 32bit PCI risers that I saw on eBay, Aliexpress or elsewhere had any form of shielding on them. I found it was necessary to add my own shielding to the cable, otherwise I ended having a lot of issues. I did it with some normal copper tape used in electronics and wrapped that in electrical tape to insulate it, and worked a treat since.

I'd imagine that the sound card would require the same treatment if you get one.

With the keyboard, whatever interface it is, there's likely some converter kit or cable out there.

Would really love to see you pull this off.

Here is an idea.

You could always use a larger case and then put a smaller laptop motherboard in there.

Then use a pcmcia to 2 PCI slots adapter.

Magma makes them.

And how would you get an AWE64 in there? That would require ISA.

The other option would be to use an older laptop that has a dock available that has PCI and/or ISA slots available and then mod the laptop case to mount the dock right on the laptop itself.

Dell has a version of the D-series dock that has a PCI slot. The model is PD01X
http://www.dell.com/downloads/us/products/lat … ily_docking.pdf

Here is a thread with some models of laptops/docking stations that had ISA slots.
Old notebooks with ISA slots or docking stations with ISA slots

Some of the old HP Omnibook laptops had a docking station with an ISA slot as well.

Get a Industrial Portable Case.

There are one's that fit easily a Mainboard and some slots..
also with Monitor integrated.

EDIT:
http://www.ebay.com/itm/Kontron-Power-Lite-Ru … D-/112392615741

Such Machines often have pci slots..
and the Display is wired to mainboard, you simply have to lift vga wiring and wire it to 3dfx and the 3dfx to the mainboard.
i have such a Industrial Computer and it uses default vga screen.
but mine has isa slot..

You could get one of those portable Xbox360/Playstation3 cases that have the built in LCD. Then just build a PC from a SFF case that's the approximate size of one of the consoles and use an HDMI to VGA+Sound adapter. and have a small keyboard and mouse. Might not be exactly like a laptop but it would be portable.

https://www.newegg.com/Product/Product.aspx?I … N82E16879003001

https://www.newegg.com/Product/Product.aspx?I … N82E16812186169

Found this. I wonder if they would let someone just buy the chassis!

http://www.theportablepc.com/commanderat3.html