My old equipment :)
The L40SX took off in February 1991. I found information that it was actually designed in Scotland and it was the first real portable IBM computer or notebook or laptop like we are talking today. There is a huge difference between the L40SX and its famous predecessor P75, especially when it comes to weight. The colors of previous models have been preserved.
Work comfort is much better because you can use an open laptop while holding it on your lap. To reduce the dimensions, the numeric part of the keyboard was abandoned. But it was possible to connect an external numeric keypad module.
In order to control the energy in this model, the transition to inactivity of the laptop was taken after closing the screen. During operation, the clock frequency can also be adjusted automatically to the power needed for the program being run.
An interesting feature is the built-in interpreter The IBM Personal Computer Basic Version C1.10, ie that the L40SX computer can be run in DOS mode or under Basic control - a screenshot in the gallery.
On page 23 Quick Reference there is information regarding the expansion of L40SX memory:
Memory Module Kit:
Updating the computer's memory size is achieved by installing 2MB, 4MB or 8MB of memory in two-module expansion kits.
The memory connectors are inside the computer (blue in the pictures).
Note: You can not choose a combination of two 4MB memories. Module sets: select one 4MB- and one non-4MB module memory for the set.
This laptop needs to be configured for a floppy disk with setup - I used Reference Diskiette Version 1.03.
I think that in Quick Reference you will find many answers.
Parameters IBM PS/2 Model L40 SX:
80386 processor with 20 MHz clock and space for coprocessor
A hard disk with a capacity of 205MB.
Probably there is no sound card - there is a so-called in buzzer.
Memory of 2 MB on the board + two free connectors for memory type PS/2 SIMM 2,4,8MB.
Floppy drive 3,5 "1,44MB.
VGA mono screen
Output for external color monitor
Battery Ni-Cd 10.8V, 2.4Ah, Model P/N 79F0197, liked to pour it, so you have to take it out in the old exams. I had two copies and both had traces of crossings with a spilled battery.
Power supply 15V - 2.7A - AC Adapter IBM Model P/N 65F0218 in the photos original IBM.
Useful (I was here and checked):