IBM's latest supercomputer is hooked up to the watercooler.
Big Blue has come out with a new version of its high-end supercomputer, the Power 575, which can provide five times the performance of its predecessor on 40 percent of the power. A fully stocked Power 575 rack contains 448 processing cores.
A substantial part of the decrease in power consumption is due to a water cooling system that brings in chilled water from the outside, runs it through copper plates located above individual processors to absorb heat, and then draws the water out so it can expel the heat outside of the computer.
By getting rid of heat in this manner, the air conditioning requirements are greatly reduced for the "hydro cluster" 575. Air conditioning can account for roughly half of the power consumed by data centers. Conversely, instead of cutting electricity consumption, IBM, or one of its customers, could squeeze in more computing power into the same room and keep the air conditioning constant.
Computer makers have employed liquid cooling in various ways over the decades. Many liquids, and particularly water, can hold far more heat than air. Similarly, architects and building owners are experimenting more with liquid cooling and heating systems as energy prices rise.
"Water is about 4,000 times as efficient as air to cool a system," said Ross Mauri, general manager of Power systems at IBM.
The effectiveness of a water cooling system, however, depends largely on two parameters: how close you can get the fluid to the hot component and how cool you can get the liquid. In general, the closer the fluid to the chip and cooler the initial temperature, the better it works.
IBM, Hewlett-Packard and others have created blade server racks with integrated chilled water tubes. Chilled water circulates through the pipes but can't get as close to the hottest components.
The company has also created liquid cooling systems that fit inside computers and sit directly above hot components. These systems, however, have consisted of self-contained liquid vessels. The fluid heats up, rises, and then sinks again, but it stays moderately warm.
With the hydro cluster, "there is always chilled water in the system," Mauri said.
IBM isn't alone in its pursuit of brining liquid close to the chip. In February, the Tyndall Institute, a government-funded lab and incubator in Ireland, showed us an silicon impeller that can bring cooled liquids in close contact with chips. The impeller measures a few millimeters across.
The computer, along with a new Power 595 Unix server, sports a 5GHz chip, a speed bump over the existing 4.7GHz versions that have been on the market.
Unix and RISC servers, IBM wants you to know, aren't dead. In 2007, industrywide Unix server revenue grew 1 percent, Mauri said, the first time the market has grown in six years.
IBM also has been aggressively taking share from competitors Sun Microsystems and Hewlett-Packard, he added. In five years, IBM has gained 11 percent in market share, according to IDC numbers cited by Mauri, while HP and Sun have lost share.