A Cray-1 supercomputer replica from 30 "obsolete" Mac Minis (arstechnica.com)

52 pointsby pseudolus2 days ago22 comments

TrevorFSmith 4 hours ago

I know it's pedantic but this is a tribute or a re-envisioning but it's not a replica.

amelius 3 hours ago

Isn't the limit of supercomputing more about the data link speed than about the actual node compute speed?

bitfilped an hour ago

I don't get it, an actual Cray-1 getting refurbed would be much more exciting.

ginko 4 hours ago

>The Cray-1 team hopes to fill the currently empty second half of the tower through a crowdfunding campaign to secure 70–80 additional M4 Mac Minis. The goal: create a cluster capable of ranking on the TOP500 supercomputers list.

Is ~100 Mac Minis really all it takes to get into the TOP500 these days?

gs17 4 hours ago

I don't think so, the lowest from 2026 was still 2.66 PFlop/s, so they'd need thousands of Mac Minis. The M4s in the Minis aren't on a different level than the Xeons in those old clusters (outside of power consumption), even if we let the Macs use FP32.

mat_epice 4 hours ago

Pretty sure not, especially since it requires 64-bit floating-point, so the GPU cores don't help. #500 right now is 2PF. One Mac won't do anywhere near 20 TF. Google tells me you can get 350GF of DP from one 10-core M4, so you might need 10,000 to get there. Then there's the network...

mrlonglong 13 hours ago

They could rent out all that compute to subsidy the museum running costs.

eric__cartman 5 hours ago

I doubt distributed compute in a bunch of old i7s is worth much once you factor in the electricity cost

bigyabai 5 hours ago

The RAM shortage is bad, but not that bad (yet).

mrlonglong 3 hours ago

You think it's bad now?

New 48GB DDR5 ECC UDIMM chips are retailing for £2.5K each in the UK.

gs17 4 hours ago

Rather than rent it out (maybe some people would pay a few bucks a year for novelty web/mail hosting, but it's both too much and too little for most use cases, running the program of renting it probably eats up a lot of the revenue), maybe they could give compute time to universities for free, with the requirement that they provide some sort of display for museum visitors? There's probably some people with Monte Carlo simulations that could benefit from a lot of cores (if they get the M4 upgrade) while being on a student budget of $0. And if no one has requested it, they could run some BOINC project that has a nice visualization.

mrlonglong 3 hours ago

Yeah all good ideas, hope they take up some of these.

ck2 4 hours ago

imagine showing even the first iphone to a Cray engineer in 1976

they'd lose their minds lol

(Cray-1 was 160 megaflops, smartphones are teraflops)

mat_epice 4 hours ago

The Cray-1 was measured on 64-bit FLOPS, so you would have to do apples-to-apples (heh). A modern iPhone can do 300 GF of 64-bit, so only 2000x.

The iPhone 4 was probably the first that could beat a Cray-1, and it was by a narrow margin. However, that was only a 32-bit chip. The next year iPhones went 64-bit, and it was all over.

ciupicri 3 hours ago

There is also the issue of cooling. The iPhone will need extra cooling in order to function at full speed for more than a few minutes.

gcanyon 3 hours ago

We live in an amazing era, where the limit to what we can do is (almost?) more what we can imagine to do than what we are actually able to do.

dmd 2 hours ago

oh, but a man's reach should exceed his grasp. Or what is a heaven for?

brewtide an hour ago

I phrase this to my kids in a different way, but same exact sentiment: The only limit these days is a modest amount of resources and the ideas in your head.

ie. Feature film? Sure. Music album, sure. Your own electronics project designed at the kitchen table, ordered from china, housings printed on the 3d printer -- all from the table.

It is an absolutely astoundingly low bar of entry these days to almost anything you'd like to create or build.

mietek 34 minutes ago

What is worth creating when anyone can create anything?

ck2 2 hours ago

I genuinely love r/TheyDidTheMath corrections, thank you!

(now calculate it in iphone charger plug computing power heh > lunar lander)

bigyabai 3 hours ago

I don't think they would be that surprised. Look at the inside of the Cray-1: https://thumbs.dreamstime.com/z/inside-red-yellow-cray-super...

If you were an engineer working on this machine, it was visually clear to you that the modularity took up the majority of the space. The ICs themselves were already pretty dense.

latchkey 4 hours ago

The picture with all the cables everywhere... ugh that sets off my OCD.