PS/55 Note N51 SX and SLC

Details: Published: 14 May 2025

After the successes of the original note (1st Gen), the N23 (2nd Gen) and the N33 machines, two machines share the third generation space - the still-monochome MCA N51 and TFT Colour, ISA C23V.

The obvious additional branding of the type of CPU was common at the time with IBM, sticking the words 486 and/or SLC or SX after the model name on the badge to pitch it's CPU's specification.

N (for Notebook) 51 would have become the (4th Gen) N52, which is the iconic Thinkpad 700C, except it didn't. Due to the fact the C23V adopted the C for Colour and M for (possibly unreleased) Mono, we have theorised the C52 is for Colour and M52 would have been monochrome (like the 700C and 700). Of course the N51 still lacked the killer TFT display (oddly present in the C23V) and killer portable pointing device first found in the C52.

A big change from the original notes (including the N23, N33 and C23V) was the change from ISA bus to MCA, making this machine a little harder to restore.

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