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45°C cooling design cuts data center water use to near zero

blogs.nvidia.com

331–340 of 450 posts

Re: 45°C cooling design cuts data center water use to near zero

#331
post #256

Earlier quoted context omitted.

This has also one of the arguments against AC in France, shame on you for wanting to moving the hot air from inside to outside.

It’s pretty incredible, especially given that the free education in France is actually rather decent.

They're also missing the winter bit, where an AC heatpump needs three ou four times less energy than a resistive heater ... oh well.

Re: 45°C cooling design cuts data center water use to near zero

#332

Earlier quoted context omitted.

My partner lamented the same thing... Cray was doing this 40+ years ago

Cray used Fluorinert, a chlorofluorocarbon. So not exactly a environmentally friendly solution.

That shouldn’t be a problem then given that we don’t care about environmental impacts anymore.

Re: 45°C cooling design cuts data center water use to near zero

#333

> In the right geography — somewhere with reliably cool outdoor air Aaahh, there’s the catch. “Save resources on cooling by building your data centre somewhere cold, and pollute the surrounding environment by dumping your waste heat wholesale into that!” Good job Nvidia, I almost thought we had something good there.

Maybe, that's why they want Greenland so bad. Low temperature, many free spaces, no significant nature and if there is one, not enough citizen who can complain. And if they still need water for cooling, there is probably enough from the melting ice they can use.

All the money they save on water cooling will be spent on massive undersea fiber lines to move the data to and from the island.

Re: 45°C cooling design cuts data center water use to near zero

#334

Earlier quoted context omitted.

Why would a citation be needed?

https://en.wikipedia.org/wiki/Burden_of_proof_(philosophy)

Never really like this because it feels some arbitrary as to what counts as making a claim. Human language is filled with implications, and those implications are filled with implied claims. Yet burden or proof seems mostly used when someone makes one of those implied claims explicit, say by explicitly rejecting one.

"We should do X."

"X is not possible."

There was an implied claim that X is possible and an explicit claim that X is not possible, but often it feels that in such a scenario, it is the second individual who is deemed having a burden of proof.

This is made all the worse that there is rarely a single implied claim, but more a group of related implied claims that are also weighted. Like some combination of "data centers don't destroy the environment" and "or maybe they do, but only in amounts of destruction that are tolerable compared to human behaviors and worth the outputs gained" and even "they modify the environment, but it doesn't count as destruction, just change". And even worse (yet again), different readers of the conversation will find themselves placing different weights on these different interpretations making it near impossible to agree on what the original claim is. Thus the first person who makes an explicit claim gets all the attention which ignores all the messy implied human communications preceding it.

Re: 45°C cooling design cuts data center water use to near zero

#335

Earlier quoted context omitted.

I’d love that heat in the winter. Imagine, free heat! Linus heats his pool with excess cpu heat. It’s all about using things wisely and not panicking. AI and datacenters are here to stay, you can’t fight them, but you can leverage their waste for profit.

"Everyone will be living in the metaverse by 2025, you can't fight it so might as well buy virtual property near Snoop Dogg" It takes one recesssion and all datacenter spending will get rolled back. Yes technology will not go away, AI has been here for over many decades that doesn't mean the current paradigm will continue always and exactly the same forever into the future. If history shows us anything its that parad…

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Re: 45°C cooling design cuts data center water use to near zero

#336
post #29

Earlier quoted context omitted.

I’ve been to datacenters, but not the huuuge ones people seem to talk about in the context of AI. They are noisy inside (due to air cooling, which is largely avoided by the tech in the OP), but they’re entirely unremarkable outside compared to any other commercial or industrial building. Computers are not inherently loud, nor is power conversion. Power plants are all over, even in populated areas. They’re not so bad…

Look up Benn Jordan's video on datacenter infrasound. Just because you can't perceive the noise doesn't mean it's not there and it doesn't have an effect on the human body, especially over very long periods of time.

I was a regular viewer of Benn Jordan until seeing one of his videos about how Apple sucked because the iPad was incompatible with so many MIDI and DAW controllers. He went through his devices one by one, plugging them into the iPad and then showing that the iPad didn't recognize the device.

I thought it was a joke of some kind and eventually he would give the "reveal" but no, he finished the video without ever considered that USB is a host/device connection - and although USB-C confusingly introduced a symmetric cable, you cannot connect two devices back-to-back (one end has to be a host) and expect anything useful to happen. And that's why Apple sells a "camera" kit to allow an iPad to act as the host to USB devices.

Seeing him use an oscilloscope to diagnose an Ethernet issue in an earlier video had given me the expectation that he was technically knowledgeable and interesting. So it was shocking that he could present conclusions with such a confident and knowledgeable air, having missed such a basic and fundamental fact about USB.

And there was no push back in the comments that I could see at the time - so seemingly half a million viewers would have finished the video feeling they had learnt something.

Re: 45°C cooling design cuts data center water use to near zero

#337

> In the right geography — somewhere with reliably cool outdoor air Aaahh, there’s the catch. “Save resources on cooling by building your data centre somewhere cold, and pollute the surrounding environment by dumping your waste heat wholesale into that!” Good job Nvidia, I almost thought we had something good there.

With LLM latencies, you won't notice it much.

Re: 45°C cooling design cuts data center water use to near zero

#338
post #161

Earlier quoted context omitted.

As someone else noted - it's effectively zero compared to the water evaporated in evaporative chillers. But it's still misleading. The major source of water use in datacenters, by _far_, is the water used in power generation. This improves PUE, which reduces power draw, but the savings are almost certainly under about 20% given that many modern datacenters already operate at a PUE of under 1.2. So if you're running o…

Can you explain what PUE stands for? I am lost.

Sorry! Power Usage Effectiveness. It's a measure of the overhead of delivering power to the servers (or motherboards, depending on how you measure it), taken to include all other datacenter power overheads: AC/cooling, UPS losses, and sometimes transformer/rectifier losses.

A PUE of 1.2 means that for every watt of power you're using in a server, you're using 1.2 watts drawn from the grid (approximately). Those extra 0.2 watts are being spent on cooling and other things.

Re: 45°C cooling design cuts data center water use to near zero

#339

Why only 45? And why water cooling? It strikes me that building everything around room temperature or slightly chilled air is a strange choice. This is already 290K-300K or so, and now this is suggesting that things run fine at 320K or 330K? I've wondered why we couldn't just design everything to operate around 200°C and just use free-cooling by pumping ambient air through. Why don't data centres look more like chick…

Semiconducting materials have relatively small band gaps, they are insulators that take very little additional energy to become conductors. In contrast good insulators incinerate before they start conducting (or turn into plasma).

Energy being energy means that high enough ambient heat can kick electrons into the higher orbitals because the band gap is so small. This also happens at normal ambient temperatures, but those electrons don’t make it very far and there aren’t that many. At 200c a closed gate is not stopping enough electrons from moving through it anymore.

At least this is the slightly hand waved technical explanation. Project in Flight on Youtube has an excellent video on how semiconductors work.

Re: 45°C cooling design cuts data center water use to near zero

#340

Earlier quoted context omitted.

They were banned in my country through a democratic process. Ofcourse it is easier when they are all owned by foreign companies lol. If they actually made money and provided jobs (lmao) it might be different.

Which country? Did they also ban AI use to be coherent?

I don't see why it would be incoherent to ban datacenters but not AI use.
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