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Data centers are transitioning from AC to DC

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Re: Data centers are transitioning from AC to DC

#291

Post by elif »

Animats wrote: post #118

800V to each rackmount unit, with hot plugging of rack units? That's scary. The usual setup at this voltage is that you throw a hulking big switch to cut the power, and that mechanically unlocks the cabinet. But that's not what these people have in mind. They want hot-plugging of individual rackmount units. GE has a paper about the power conversion design, but it doesn't mention the unit to rack electrical and mechan…

As long as you can control for fire, electrical safety seems like a temporary condition as robots and intelligent machines are cheaper and more available long term solution to hot swap blades in datacenter racks.

Re: Data centers are transitioning from AC to DC

#292

Post by riedel »

Animats wrote: post #118

800V to each rackmount unit, with hot plugging of rack units? That's scary. The usual setup at this voltage is that you throw a hulking big switch to cut the power, and that mechanically unlocks the cabinet. But that's not what these people have in mind. They want hot-plugging of individual rackmount units. GE has a paper about the power conversion design, but it doesn't mention the unit to rack electrical and mechan…

An EV fast charger can do 1000V, so with a bit of logic that sounds doable.

Re: Data centers are transitioning from AC to DC

#293

Post by adrian_b »

ta9000 wrote: post #160
teleforce wrote: post #121

Earlier quoted context omitted.

>It is absolutely stupid to talk about this as edisons revenge. If Tesla had the modern high power transistors needed to get high voltage dc out of the ac produced from a spinning turbine he would be all for high voltage dc too. This! The soon people realized these facts the better. The pervasive high rise buildings did not happen before the invention of modern cranes. Exactly twenty years ago I was doing a novel res…

Does that mean when we run out of Ga there are no more LED TVs?

Gallium is expensive to extract because it is extremely diluted in the environment.

It accompanies in very low quantities aluminum and zinc, so it is extracted only in the mines of aluminum or of zinc, as a byproduct.

However, the abundance of gallium is similar to that of lithium, while gallium is used in smaller amounts, so there is no risk to not have enough gallium in the near future.

On the other hand, all semiconductor devices with gallium also use some indium. Indium is used in even greater quantities in all LCD or OLED displays, to make transparent electrodes.

Indium is an extremely rare element in the entire universe, comparable with gold, so for indium there is a much greater risk that its reserves will become insufficient.

This could be mitigated by extracting such critical elements from the dumped electronic devices, but this is very expensive, because only small amounts of indium are used per device, so very large amounts of garbage would have to be processed in order to extract a sizable amount of it.

Re: Data centers are transitioning from AC to DC

#294

Post by mrguyorama »

crote wrote: post #193
stego-tech wrote: post #8

I've been hearing this line for over a decade, now. "Immersion cooling will make data centers scale!" "Converting to DC at the perimeter increases density!" Yes, of course both of those things are true, and yes, some data centers do engage in those processes for their unique advantages. The issue is that aside from specialty kit designed for that use (like the AWS Outposts with their DC conversion), the rank-and-file…

As seen on HN a few days ago, immersion cooling is dead: turns out the risks of getting sued to oblivion due to widespread PFAS contamination isn't worth it. [0] DC doesn't have such a killer. There are a decent bunch of benefits, and the main drawback is gear availability. However, the chicken-and-egg problem is being solved by hyperscalers. Like it or not, the rank-and-file of small & medium businesses is dying , a…

They poison water supplies, knowingly, for decades, and it only takes $12 billion dollars to finally get them to stop?

Fucks sake.

Re: Data centers are transitioning from AC to DC

#295

Post by _zoltan_ »

otterley wrote: post #7

DC power has been an option for datacenter equipment since I was a young lad racking and stacking hardware. Cisco, Dell, HPE, IBM, and countless others all had DC supply options. Same with PDUs. What’s old is new again. See e.g. https://www.dell.com/support/kbdoc/en-us/000221234/wiring-in...

800V DC is definitely not "old".

Re: Data centers are transitioning from AC to DC

#296

Post by _zoltan_ »

stego-tech wrote: post #8

I've been hearing this line for over a decade, now. "Immersion cooling will make data centers scale!" "Converting to DC at the perimeter increases density!" Yes, of course both of those things are true, and yes, some data centers do engage in those processes for their unique advantages. The issue is that aside from specialty kit designed for that use (like the AWS Outposts with their DC conversion), the rank-and-file…

I recommend reading these two:

https://developer.nvidia.com/blog/nvidia-800-v-hvdc-architec...

https://blogs.nvidia.com/blog/gigawatt-ai-factories-ocp-vera...

almost everybody in the industry is embracing 800V DC mostly because of Vera Rubin and the increased electricity requirements.

Re: Data centers are transitioning from AC to DC

#297

Post by adrian_b »

margalabargala wrote: post #248
bananaflag wrote: post #206

Earlier quoted context omitted.

On the other hand, it is possible to run out of a metal when all of it is either somewhere in some device or scattered among landfills (i.e. not concentrated in a place like a mine).

It's a byproduct of aluminum production. The earth's crust is 8% aluminum. We will have bigger problems before hitting this one.

That is true, but gallium is present in the aluminum and zinc ores only in minute quantities.

We will not remain without gallium, but it is impossible to scale up the gallium production to a higher level than provided by the current productions of aluminum and zinc.

So there is a maximum level of gallium that can be used per year and it would not be possible to increase the production of blue and white LEDs and of power transistors above that level.

Fortunately, the amount of gallium used per device is very small, so it is not likely that we will hit that level soon. A much more serious problem is the associated consumption of indium, for which the resources are much less.

Re: Data centers are transitioning from AC to DC

#298

Post by QuantumGood »

elif wrote: post #291
Animats wrote: post #118

800V to each rackmount unit, with hot plugging of rack units? That's scary. The usual setup at this voltage is that you throw a hulking big switch to cut the power, and that mechanically unlocks the cabinet. But that's not what these people have in mind. They want hot-plugging of individual rackmount units. GE has a paper about the power conversion design, but it doesn't mention the unit to rack electrical and mechan…

As long as you can control for fire, electrical safety seems like a temporary condition as robots and intelligent machines are cheaper and more available long term solution to hot swap blades in datacenter racks.

I think you're being downvoted for speaking of a complex future possibility ("robots and intelligent machines ... solution") as if it was a proven commodity. There will be many twists and turns in the path to the possible reliability, scalability, and cost effectiveness of robots and intelligent machines.

Re: Data centers are transitioning from AC to DC

#300

Post by t0mas88 »

riedel wrote: post #292
Animats wrote: post #118

800V to each rackmount unit, with hot plugging of rack units? That's scary. The usual setup at this voltage is that you throw a hulking big switch to cut the power, and that mechanically unlocks the cabinet. But that's not what these people have in mind. They want hot-plugging of individual rackmount units. GE has a paper about the power conversion design, but it doesn't mention the unit to rack electrical and mechan…

An EV fast charger can do 1000V, so with a bit of logic that sounds doable.

EV chargers take a different approach. There is no power on the connector while you're plugging it in. It then locks in place before the contactor closes and power is delivered. Unplugging is the same, power is removed before the plug is unlocked for release.
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