Mag World - Mag Computer

Episode 8: Mag Computer

Saul and Mike climb the mag scale of computing, using RAM as a proxy for compute power, from the Apollo guidance computer and the Apple II up to today’s machines, and what each mag of memory made possible.

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[This episode sponsored by the Recurse Center.]

A Mag History of RAM (1960–2025)

RAM is a good proxy for computing power. Here’s every mag of memory from the Apollo Guidance Computer up to today’s machines — Nintendo, PlayStation, iPhone, and more. Remember, this is a log scale. (full write-up)

Transcript

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[0.8s] Saul : Hello and welcome to Mag World, where we like to ask big questions, make wild guesstimates, and quantify literally everything on a magnitude scale. Just remember that every order of magnitude is a big deal, because as we say at Mag World, quantity has a quality all of its own. If you wanna learn more about Mag World, come visit our website at magworld.pw. I’m Saul Pwanson, your guide to Mag World, and I’m here with my friend Mike, who’s used a computer.

[27.5s] Mike : Yes, and I’m curious, are we going to use this one here during the episode? Should I turn it on?

[31.8s] Saul : Yes, please do.

[32.5s] Mike : All right.

[47.8s] Saul : So today’s episode is Mag Computer. The good old Apple II booting up. Um, actually, we’re gonna need to be online for this. Could you log us onto the internet, Mike?

[01:01.1] Mike : Uh, yes, yeah. All right, give it a couple minutes, but then we’ll be there.

[01:17.1] Saul : It’s not that long. Okay, here we are. We’re online now. So computers are one of the topics that inspired Mag World in the first place. I mean, I’ve loved computers basically since I was born, and each magnitude of computer that I’ve experienced has had a quality all of its own.

[01:35.2] Mike : Will you kind of explain to me what these different mag levels of computer are?

[01:42.0] Saul : Yes, great question. So I use RAM as a proxy for compute power. Gordon Moore, you’ve heard of Moore’s Law?

[01:51.1] Mike : Absolutely. It’s something about the doubling time for processing power, something like that.

[01:57.0] Saul : It’s actually about the density of transistors, that you’ll have m- twice as many transistors on an integrated circuit, and th- th- that doubling time being, I think, 18 months initially. And this was initially specified in 1965 and then revised in 1975 to be every two years instead. But it’s held true, or it did hold true, for some 40 years, and it might be flattening now, I guess we’ll still see. But the fact that it held true for so long is this exponential rise of compute. And because it’s about transistors, you need transistors both for computing power and for memory, and they kind of go hand in hand. So as your compute power goes up, so does your memory, and it turns out that you, you need more memory also to do more complicated things. Like, even if you’ve got the, the fastest possible computer but a very little amount of RAM, you can’t do very much with it, no matter how powerful it is. And so, yeah, I use RAM as a proxy for compute power, and order of magnitude RAM. So a mag 4 computer would be an Apple II that had 32 or 64 kilobytes of RAM, and then a mag 5 computer would have some hundreds of kilobytes, up to the classic 640K of RAM thing, and et cetera.

[03:17.8] Mike : Okay, great. So we’re using RAM as this proxy, uh, for computing.

[03:23.7] Saul : Mm-hmm.

[03:24.4] Mike : And RAM is an active memory rather than a storage memory, is-

[03:30.1] Saul : Yes

[03:30.3] Mike : … my understanding.

[03:31.4] Saul : Good point, yeah. So the iPhone is a mag 9 computer in my, in this nomenclature. It has a gigabyte of RAM, maybe four or eight gigabytes of RAM. It turns out the most recent ones, uh, are, like, now, I think, 12 gigabytes of RAM. But they have, uh, not only that spec of RAM, the working memory like you’re talking about, they also have the storage, which is like your, your hard disk or your USB drive or something, right? And that’s more like the, the paper that you’re writing down as opposed to the, the brain memory that you have, the working memory that you have in your-

[04:03.2] Mike : Mm-hmm

[04:03.8] Saul : … mind.

[04:04.9] Mike : Okay, great.

[04:06.5] Saul : So I went to the Recurse Center a couple weeks ago.

[04:08.9] Mike : Oh, what’s that?

[04:10.0] Saul : The Recurse Center is a retreat for programmers. People go there who are interested in computing and computing technology, and they spend somewhere from, like, six to 12 weeks being in this community of like-minded people who are curious and interested about computers and becoming a better programmer. And I went through this program actually back in 2017, and it’s really a remarkable community, and I wanted to say that this is why we met.

[04:38.0] Mike : Tell me.

[04:38.6] Saul : I did this program in...