| HN Mirror

Y	Hacker News new \| ask \| show \| jobs


	by fooker 143 days ago
	> Can people please try and use their fucking brains for a second? Have you considered that people smarter than you think it is plausible?

2 comments

youarentrightjr 143 days ago

> Have you considered that people smarter than you think it is plausible?

I know many people smarter than me, plenty of them who have spent careers building data centers, and not one of them think this is plausible.

You should consider whether people smarter than the average investor are pulling a fast one.

link

fooker 143 days ago

Maybe we are talking about different things here?

I don't doubt spacex can fail at this.

I also don't doubt we are fairly close to making this plausible.

> plenty of them who have spent careers building data centers

Famously, plenty of people who have spent careers building rockets would swear that reusable rockets would absolutely never work.

link

fluoridation 143 days ago

>I also don't doubt we are fairly close to making this plausible.

Maybe you should doubt that. There's literally no reason to think this is plausible besides some hype merchants' say-so.

link

fooker 143 days ago

> some hype merchants

Excluding Spacex:

Nvidia, Google, China, European Commission, Blue Origin

And this being HN, a YC funded company has put a single GPU rack in space and demonstrated training a reasonable sized model on it.

But yeah, it's all hype, sure.

link

youarentrightjr 143 days ago

On the off chance you're sincere and not just heavily over indexed into Elon stocks:

It's trivial to understand why this is all hype if you pay attention to physics, as another commenter suggested earlier.

https://en.wikipedia.org/wiki/Stefan%E2%80%93Boltzmann_law

Assume you're radiating away the heat for a single B200 (~1kW), and the max radiator temp is 100C, you find A = ~3m^2.

So that's 3 square meters per GPU. Now if you take into account that the largest planar structure deployed into space is ~3k m^2 (https://investors.lockheedmartin.com/news-releases/news-rele...), you're looking at 1000 GPUs.

That's a single aisle in a terrestrial data center.

Cost to deploy on earth vs satellite is left as an exercise to the reader.

link

fooker 143 days ago

You are missing one important thing here.

You do not radiate all the heat away from a GPU, a modern GPU can run pretty hot. Also look up how this is getting better for the next generation of GPUs.

Maybe repeat your calculation with updated assumptions?

But even if you were completely right, your argument is that we can't do this tomorrow, yes I agree. Typical technology development cycles are about 5-10 years.

link