cooling posts

Ahh, the data center's heart and brain, the server room. Dim, cavernous, off-limits to most of our coworkers, and bathed in the soothing dual ambiences of CPU fans and high-powered air-conditioning, they're the perfect place to take a moment to cool off after a tough call or a sprint across a plague-wracked parking lot. All those boxen, miles of Cat6 just the way we want it, chilled to a component-friendly sixty-something degrees.

Well, so much for that particular workplace fantasy. We've spoken previously about the positive aspects of greener, more energy-efficient computing, but now they've gone too far. Folks have finally noticed that facilities cooling is one of the biggest costs for server rooms and data centers, and the thermostat is being kicked up to save money. Way up.

I must not overheat.
Heat is the chip-killer.
Heat is the thermal death that brings total obliteration.
And when it comes, I will turn the fans on to speed its path.
Where the heat has gone, there will be processing.
Only my FPS will remain.

Last week, we talked about the importance of feeding enough watts to your components to allow them to perform their best. The other side of that coin is dealing with the waste heat that is a byproduct of all that high-speed math. Heat's pretty much as far down the entropy scale as you can get -- most of what we do turns organized energy, one way or another, into heat. The problem with this state of affairs, at least for electronics, is that they are happier the colder their environment is.

We here at Big Download naturally assume you like free stuff. That's why we've got that enticing heap of files up there, batting its eyelashes seductively at you (or maybe I need to switch to decaf that isn't laced with wormwood). But, chances are, free (as in beer) stuff is lurking on or under your desk right this moment. No, not the cans with the five cent deposit. No, not that copy of Daikatana you forgot to take to the pawn shop, either.

Unless you're already at the bleeding edge, got exceedingly unlucky, or are highly risk-averse, there's extra performance to be had out of the components you've already got by running them faster than their rated, factory-set speed. This practice is known as overclocking, and has grown from a lunatic fringe cottage industry into big business, frequently with the tacit approval of component manufacturers, and occasionally engaged in by some brands themselves.

In a nutshell, overclocking allows you to get the performance of a more-expensive part -- CPU, video card, or RAM module -- out of a less-expensive one by the strategic application of brains, willpower, voltage, cooling, and luck.

On NPR this morning, there was a delicious little item talking about something that is, canonically, Big Iron. IBM has taken the wraps off of bluefire, their latest supercomputer. After its shakedown period, it's expected to be one of the 25 most powerful supercomputers in the world, capable of 76 teraflops (76 trillion floating-point operations per second).

To get there, it sports the new POWER6 microprocessor, which has a clock speed of 4.7 gigahertz. "So what?" I hear some of you saying, "Supercooled home PC systems have been topping 5GHz for a while now." The difference here is that bluefire consists of 4,064 processors, 12 TB of memory, and 150 TB of disk storage. That's certainly impressive, but not enough by itself to land bluefire here at Big Download's hardware HQ. No, what caught our attention is what sets bluefire apart from other supercompters, including the three (!) it's replacing, is that it's water-cooled. That's right, ladies and gentlemen, one of the open secrets of home-brewed system tweaking has hit the big time. IBM reports that the move to watercooling has allowed them the double bonus (which many of us already enjoy in our home boxes) of being able to run faster processors, while at the same time, saving energy to keep it running at a stable temperature. IBM says that bluefire uses 33% less energy per rack than the equipment it's going to replace.

"We're especially pleased that bluefire provides dramatically increased performance with much greater energy efficiency." -- Tom Bettge, director of operations and services for the National Center for Atmospheric Research; Computational and Information Systems Laboratory.