IBM PS/WTF?
Some books would have you believe that there was the huge IBM portable designed to compete with Compaq's portable, then the iconic L40SX and then the miracle of the Thinkpad 700C occured. In reality, there was a lot more going on, with various spaces within IBM working towards the ideas which would become the iconic Thinkpad 700C with it's red nipple. IBM had released the PS/1, PS/2 and PS/55 ranges and were gradually moving away from their earlier 55xx models - which is where mish-mash of 55, PS and Note branding came from.
After the IBM 5155 "portable" and the strange IBM Convertible came....
PS/2 P70 and P75 - Cream-coloured luggable suitase-style portable personal computer which had evolved from the early CRT IBM Portables but now with lit flat-panel screens. It was only just portable and did not run on batteries.
PS/2 L40 SX - A large PS/2 laptop computer - the first IBM with a folding lid, flat-panel display, a 'good' keyboard and a battery. The display was low-energy but not very nice to use. And it was still too big. Some have said that because this machine had such a delayed development and release, lots of other machines which certainly looked more advanced quickly superceded it.
Model 5499 On-Line Note - a small, notebook-style, portable mainframe terminal.
PS/2 CL57 SX - A joint project with Toshiba (who agreed to fund half of the TFT screen purchases) - a large black trackball-equipped IBM PS/2 famed for being the first notebook with a colour TFT screen. It's too big, MCA and the trackball isn't very ergonomic.
PS/55 Note - The PS/55 was a range of 55xx model desktop computers for Japan only, based on the PS/2. The 'Note' branding suggested a Notebook version.
- Model N23SX (5523-S) (03/1991) (similar to the western PS/2 N33SX and PS/2 N51SX models)
- Model 5535 (1987)[1]
- Model 5535-S (1990)[4]
- Model T22sx (1992)
- Model N27sx (02/1992) (Japanese-only release similar to the PS/2 CL57SX model)
- Model C23V (10/1992)
- Model C52 (10/1992) (identical to the ThinkPad 700C - basically the killer machine with the right title.
PS/2 Note - This took the Japanese 'Note' branding and applied it to the western PS/2 model range. N33 SX, N51 SX and N45 SL. These machines were almost there but lacked a trackpoint and a decent colour TFT screen. The PS/2 Note N45SL was a horrible re-badged Zenith machine. They're also completely different inside to a Thinkpad and much more evil to work on.
PS/Note -The PS/Note series included models like the PS/note 182 (A PS/1, 386SL-based machine) and then the PS/Note 425 and 425C (486-based), which were essentially the same as the ThinkPad 350/350C.
Eventually, what had evolved through dozens of flawed machines, almost getting it right in different markets across the globe, became the IBM Thinkpad 700C.
- It took the ideas of a folding-lid, high quality keyboard and low-energy display running from batteries in the L40 SX
- It took the black bento box form factor of the N23
- It took the sharp, colour TFT screen from the CL57 SX
Added a trackpoint and forward-facing drives and gave it a cool red and black colour scheme with a snappy name.And it fit inside a briefcase without poking your fellow aeroplane passender in the ribs.
...Hinges were still a creeping progression, likely solved by the 750.