Green Chips: IC Makers Looking to Cash In

Peter Singer, Editor-in-Chief -- Semiconductor International, 2/5/2008 8:33:00 AM

The global explosion in information technology, combined with rapidly escalating energy costs, has chipmakers asking how much does it really cost to run today’s computers, and what can be done to provide more energy-efficient solutions?

In remarks made last week in Brussels at a dinner convened by Germany’s Silicon Saxony group, Mario Rivas, Advanced Micro Devices's (AMD, Sunnyvale, Calif.) executive vice president of the computing solutions group, said that computers today are an integral part of people’s lives around the world, made possible by massive computational power combined with a global network and data storage. He said that the 20 million servers around the world — half of them in North America — require enormous amounts of electricity.

Rivas referred to an AMD-financed study conducted by Jonathan Koomey at Stanford (Palo Alto, Calif.; produced by a grant from AMD) that shows that aggregate electricity use for servers doubled over the period of 2000 to 2005, both in the United States and worldwide. The study, “Estimating Total Power Consumption By Servers In The U.S. And The World,” showed that almost all of this growth was the result of growth in the number of volume servers, with only a small part of that growth being attributable to growth in the power use per unit. Total power used by servers represented ~0.6% of total U.S. electricity consumption in 2005. When cooling and auxiliary infrastructure are included, that number grows to 1.2%, an amount comparable with that for color televisions. The total power demand in 2005 (including associated infrastructure) is equivalent (in capacity terms) to about five 1000 MW power plants for the United States and 14 such plants for the world.

Cooling cost will be equivalent to that of investments for new servers beyond 2010.

“That’s an incredible amount of power,” Rivas said.

The total electricity bill for operating those servers and associated infrastructure in 2005 was ~$2.7B and $7.2B for the United States and the world, respectively.

Rivas said the demand for servers will grow by more than 50% from 2005 to 2010. When a company decides to set up a data center, it’s more expensive to operate it than to buy the equipment, Rivas said. “If you can buy new equipment that’s more power efficient, the equations are very simple. You will go for the more power efficient.”

Rivas also noted the increasing amount of energy consumed by personal electronic devices than most of us consume for work or play. Laptops, desktops, cell phones, game consoles and a lot more. He said that at the recent consumer electronic show in Las Vegas, a 150" plasma TV was on display. “If you really inspect the power, it takes 10,000 W,” he said. “It’s expensive to watch a football game.”

We have made progress, but there is more to do. “AMD is in business to make money. However, having said that, we also firmly believe that it’s smart business to be environmentally friendly in the way you design, manufacture, use and discard technology.” The most energy-efficient businesses outperform their competitors by 2%, he said.  

AMD and other chip makers are seeking to produce processors with reduced leakage current, operating voltages, and less threshold voltage variability.

In a presentation made last year at the International Trade Partners Conference (ITPC) in Hawaii, Michiharu Nakamura, Fellow, Hitachi, reported that the volume of internet traffic will increase by 40% annually, and that the power consumption of routers will occupy ~9% of the total power supply of Japan in 2015 (total power supply consumption is assumed to be 920 billion kilowatt hours). He also said the cost of cooling data centers worldwide will be equivalent to that of investments for new servers beyond 2010.

Chipmakers have long been working to develop low-power ICs for mobile applications to prolong battery life. The push to more energy-efficient ICs could provide an even greater impetus to do so, and more strongly impact how conventional ICs are designed and built. To date, performance has been measured by device speed and cost/bit. Now, energy efficiency is posed to play an increasingly dominant role. More efficient ICs have reduced leakage current, operate at reduce voltages, with reduce threshold voltage variability. 3-D integration also shows promise for reducing interface power. More novel concepts ,such as optical interconnects and spin-transfer torque RAM (SPRAM), offer the potential of further reductions.

The push to low power will also impact design considerations, such as chip architecture and how instructions are sent. On the design side, multi-core CPUs outperform conventional large-core CPUs without causing power increase. In Japan, a project for Advanced Heterogeneous Multi Processor Technology Development embeds special processors as a general processor to improve performance/power efficiency.

This week at the International Solid States Circuit Conference (ISSCC, San Francisco), Intel (Santa Clara, Calif.) is talking about a new chip for mobile applications, code-named Silverthorne. Expected to become available in the second quarter, the chip draws 0.6-2 W, or roughly a tenth the power used by the chips Intel sells for laptop computers. Intel reverted to an approach called "in-order" execution, which it hasn't used in more than a decade. The design carries out computing instructions essentially one at a time, where more modern "out-of-order" designs execute multiple instructions simultaneously. While the newer approach can achieve higher performance, an "in-order" design helps reduce power consumption.

Also slated to be unveiled at ISSCC is a portable electronics-focused chip design developed by researchers from Cambridge, Mass.-based Massachusetts Institute of Technology (MIT) and Dallas-headquartered Texas Instruments (TI). They believe the chip is up to 10× more energy efficient than present technology. MIT and TI said they believe the technology could lead to cell phones, implantable medical devices and sensors that last far longer when running from a battery.

One key to the new design was a DC-to-DC converter, which reduces the voltage to the lower level, right onto the chip, and is more efficient than having the converter as a separate component, so that the redesigned memory and logic, along with the DC-to-DC converter, are all integrated to realize a complete system-on-a-chip (SOC) solution.

Of the 450 W in power a server consumes, the CPU consumes 86 W, memory 27 W and chipset 32 W. The greatest consumer is AC/DC conversion (131 W). The fan and DC/DC conversion consume 32 W each, the disc drive 72 W, and the PCI card 41 W, according to Hitachi.