Intel and SGI Test Full-Immersion Cooling For Servers

itwbennett (1594911) writes "Intel and SGI have built a proof-of-concept supercomputer that's kept cool using a fluid developed by 3M called Novec that is already used in fire suppression systems. The technology, which could replace fans and eliminate the need to use tons of municipal water to cool data centers, has the potential to slash data-center energy bills by more than 90 percent, said Michael Patterson, senior power and thermal architect at Intel. But there are several challenges, including the need to design new motherboards and servers."

Comments

Cray-2

[Anonymous Coward]

The Cray-2 did this in 1985 using a liquid called Fluorinert also invented by 3M:

http://en.wikipedia.org/wiki/Cray-2
http://en.wikipedia.org/wiki/Fluorinert

What about maintenance costs?

[Anonymous Coward]

Many years ago I invested in a Hardcore Computer Reactor system. This was a giant custom built computer that had both the motherboard and GPUs submerged in a proprietary non-conductive coolant. It weighs over a hundred pounds filled, and they still needed pumps inside it to direct the coolant across a bunch of purpose built water blocks to extract heat from the hottest components (since liquid convection alone was not enough).

About a year ago I had to replace the motherboard (which is a proprietary part). I can't even begin to tell you what a gigantic pain in the ass this was. There is a ton of plumbing running around inside the system that you have to worry about, and beyond that the entire compute module comes out of the coolant dripping wet, so you can't just pop it out and chuck it down on your desk. I had to break out a pair of rubberized gloves just to service the damned thing since it became obvious that the boards weren't going to dry themselves just sitting there- the coolant doesn't evaporate at all and you can't just take a towel to the raw PCB to clean it off. I landed up lining the inside of a large plastic bin with antistatic bags and doing the procedure there, which still made one hell of a mess.

I still run that system, but if anything else ever breaks I'm probably going to sell it off rather then try to fix it again. I honestly can't imagine trying to deal with that sort of a setup on a datacenter scale. General liquid cooling is easy enough to deal with since you can just disconnect the cooling lines and pull out a module (which is precisely what IBM does with their extreme high-end end PowerPC based servers). Submerging the entire PCB is nasty business, and I wouldn't want to be the tech who has to go through that amount of trouble on a weekly or monthly basis.

Re:Overclockers have been doing it for ages

[Chas]

Yep. Got to fiddle around with Fluorinert cooling years ago.

Interesting, just not very practical.

You really DO need a fully sealed system and ostensibly clean-room assembly. Because, while the coolant itself is non-conductive, any detritus that accumulates in the fluid after settling out of the environment ISN'T. That's the main thing about water (straight H2O) isn't conductive. It's all the other things in the water, minerals, dust, etc that's doing the conduction.

Also, as noted, there's STILL going to be use of fans and water. Because you still need systems that extract the thermal energy from the liquid medium. You simply remove them from the main system chassis.

It also doesn't change the fact that it's still a TERRIBLY inefficient way to cool the system. Unlike water cooling loops, where you have no more than maybe a pint or so of fluid cooling the major heat sources in the system, you have QUARTS of fluid basically covering everything. And you really have no good flow control, other than extremely high volume fluid exchange, which is energy inefficient in and of itself.

That's PROBABLY what a lot of the board re-engineering is about. Centralizing all the thermally active devices into a centralized area to limit the volume of immersion coolant required and to simplify flow control.