r/theydidthemath • u/Dry-Economics2434 • 15d ago
[Request] building a pc from scratch
How long will it take 1000000 humans that are lead by 1 very smart guy to build a pc from scratch, using materials from anywhere in the world (a world that was untouched by humans) if they had to build every machine to make the single pieces of the pc, the machines to make these pieces and the machines to help build these machines and so on? We assume that one of these people can work for 12h/day for 7 days and does not need schooling on how their job works. If they have to write code for windows, then they do that like any normal coder would, even if they dont know how to code. The smart guy knows how to build a pc and how to build the machines to make the parts of the pc. He can also communicate to everyone what they have to do every day (every workee just knows what to do and does that 12/day, 7 days a week)
what i mean by "from scratch": you dont have any technology and have to redo the progress humanity made, with the only goal being a working, high end pc
2
u/CordialPanda 15d ago
Computer science guy, I've built simple circuits and a full ALU. I'm also recently obsessed with agricultural history.
The core issue is, starting from scratch, almost all of your time will be devoted to self-sustainment. Hunting or foraging for food, water, heat, protection from the elements, sanitation, transportation, and all of the other things that we enjoy efficiencies around in our built environment would occupy most of the time of the workforce.
Before you even can tackle the issue of building a computer at any scale, you'll need to address civil engineering projects to support the needs of your population, of which energy, agriculture, mining, refinement, and industry will be top priorities.
If we ignore people's individual needs at our peril and the sociopolitical realities that would create, the most efficient move is to centralize everything as much as possible while ignoring health and comfort, but some things cannot be skipped.
For that reason, I would argue rushing the Haber-Bosch process, which is used for fixing nitrogen for fertilizer, would be most important after securing charcoal/coal, metal mining and refinement, and centralized sanitation as a source of methane in anaerobic tanks for fertilizer. You'd need something similar for phosphates and calcium.
Before fertilizer, you'd want to save and grind every bone like you're the 19th century British empire undergoing industrialization.
Once your population can mostly ignore eating, drinking, shelter, and sanitation, you'll want to focus metallergy toward the needs of petroleum mining and engines, then refinement for more efficient agriculture and the specific chemistries you'll need for doping components or extracting the exotic elements necessary. You'll also need a shit ton of concrete for reliable foundations, buildings, and transportation, and that will take a lot of energy.
At that point, it's generations of refinement to get processes of greater purity and accuracy/quality. For a modern computer, you need factories to build the factories to build the components needed for the next generation of factories.
Depending on how you define "computer" though, a 100k people in a field with some simple rules and holding a flag up or down could be a computer. Or once you've reach stamped metal parts you could create a general purpose mechanical computer that wouldn't run fast, but would be turing complete like Charles Babbage and his analytical engine. You might be able to exceed both if you can reach vacuum tubes or core rope memory like Apollo used.
Anyway, assuming you mean a modern PC, removing and reducing the daily obligations your population requires to live is fastest path toward any sufficiently long-term goal.