Last week I went to a different section of my workplace and in front of a storage room I've seen an old beige desktop. Didn't really look that hard, seen the Windows 95 ans Pentium stickers on the front, a specific promising looking expansion card on the back and put in some word with the lead engineer that if it's already off the books, and only in the way about to be thrown out, I'd be selfless enough to sacrifice myself and take on their burden. Today I could finally pick it up.
It's an Olivetti M4 P100. While at work investigated a little bit, the closest thing I could find was the M24 P133. Which is about the same, but to my dread, it supposed to have a soldered Dallas IC.

It's a little bit dirty, but over all in decent condition.

Opening up, my suspicions are confirmed. The promising looking card is a Sound Blaster 16. One of the earlier variants, CT1790. Now I have a third potential sound card for the 486DX4 build I've been planning to do for a good while now, but never seem to find a motherboard that doesn't cost an arm and a leg. Anyway, the inside isn't much cleaner than the outside, and luckily it has a coin cell battery. Unluckily it's still soldered. I didn't see anything catastrophic aside of some dust. It's clear the PC was upgraded at some point. I don't know if it came with the optical drive, the color doesn't match, but the manufacturing date isn't all that far off, November 1996. It's a Sony CDU311 8x speed drive. The RAM is also more than expected. It has 2×32MB and 2×something. I assume the 2×something is what it was shipped with. The heatsink is also a little bit big for what I'd expect for a Pentium 100 and glued on, I thought it was also upgraded, but no.

Since everything looked OK, I took a leap of faith and turned it on. Indeed, 80MB RAM and Windows 95 boots from the 800MB Quantum hard drive. The drive didn't have too much data. It was used by someone tasked with training... and DVD bootlegging. There was an extensive list of movies in a Word document. Also an Excel spreadsheet called "The world's most important spreadsheet"... it calculates the time you have to wait before you drive based on the amount of alcohol you drank. Based on the file modification dates, it was in active service up until about Q1 2006 which is surprisingly late for a P100.
Now I have to think about what to do with it. I'll definitely keep the SB16, and shouldn't keep the rest. But it ticks all the boxes I want from the 486DX2 PC I'm planning to build, except that it's not a 486. The On-Board Trident 9680 is a graphics chip I have no experience with, but I know it was sold as a PCI card as well. The only thing I really don't like about it is the proprietary motherboard. It's very similar in specs to my second PC, except with 2.5× as much RAM. And that I don't remember what graphics card did I have back then.
It's not exactly what I want, but I also don't want to regret selling it. It's nostalgic to have a P100 system again after nearly 25 years, but I was much more attached the one I had before and the one after.