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Green Computing Update, Part 2: Components
Jeremy Faludi, 16 Nov 07
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Part 1 of the green computing update was on data centers. This week I'll begin to describe what's happening on the level of individual machines by covering components: efficient CPUs, monitors, and power supplies, as well as greener material choices in other components.

Green Computing Hits Critical Mass

As I mentioned in Part 1, momentum is building on green computing. GreenBiz now has a portal just for this field; there's a Green PC blog, and articles on it are showing up in just about every IT publication around. The tech executive site has an excellent overview of the field by Katherine Walsh.

The rise of bright green computers is not just taking place in the Western world, either. Asia Eco-Design Electronics, a project by the European Commission, is organizing conferences in China, India, and Thailand as well as Europe to raise awareness and distribute knowledge about green electronics design.

Businesses are getting excited about green computing, with X Prize-style contests starting to appear. Last month Dell launched ReGeneration, a competition to design the world's greenest computer, aimed primarily at students but open to anyone. Prizes range from $10,000 to $15,000. And Freescale Semiconductor announced its FTF Design Challenge, offering $10,000 for "the most inventive green embedded designs" that the company could use in its chips. The biggest prize (and the soonest deadline -- the end of November) is the Live Edge challenge by Farnell & Newark, a distributor and retailer of electronic components, to invent an original electronic device/component that has a positive environmental impact. The company is offering $100,000 to fund initial manufacturing of the winner's invention, and allows the contestants to keep the rights to their inventions.

Cool CPUs

The energy issue is not just for conservationists. Moore's Law has been slowing down in the past few years, because overheating is becoming more of a limiting variable than feature size on chips. In just a year, "performance per watt" has gone from a rarely heard-of curiosity to a leading sales spec; AMD's page for its Opteron processor lists performance per watt as its first selling point. As IT Jungle writes,

The average Opteron processor running a heavy load might be rated at 95 watts, but it only burns about 70 watts of juice typically and with PowerNow features, that number can be dropped to around 32 watts in the idle state.

This self-throttling is key to improving CPU efficiency, because the CPUs in most desktop machines spend most of their time idle. Whether AMD chips outperform Intel chips is subject to enough debate that third-party testers like PC Stats go and do their own performance per watt tests. However, Intel seems to have gained the upper hand: it has just announced new chips with feature sizes of 45nm, which Gordon Moore called "the biggest change in transistor technology in 40 years." What's more, Intel announced at this past February's International Solid-State Circuits Conference (ISSCC) that it has made an 80-processor chip that can do one teraflop at 98 watts. The catch is that this processor isn't compatible with any existing desktop or server architectures; it was a research project.

Sun is still in on the game with its Niagra processors, and IBM has joined the fray with its' Power6 chip for servers.

Despite Intel's announcement, the leader in the efficiency fray still appears to be startup PA Semi, which is producing chips that can do 2Ghz at just 25 watts.

Quantum Computing

The quest for energy efficiency is opening up a whole new discipline in chip design. As an Ars Technica commentator stated in relation to the ISSCC conference, "if I actually understood more than 25 percent of the gory details of how any of the presenters -- Intel, AMD, PA Semi, or Sun -- are cutting down on power consumption right now, then I'd quit writing about these chips and get paid lots of money to design them." But the future holds power efficiency disciplines that are even further afield under the rubric of reversible computing, including quantum computing. Reversible computing promises to cut power consumption by perhaps a thousandfold, and quantum computing also promises the capability of solving massively parallel problems that are effectively unsolvable by normal computers, such as large number factoring for cryptography.

There appears to be little recent news in the field of "normal" reversible computing (although last year American Scientist ran a good in-depth description of what it is and why it would radically improve CPU performance per watt). Surprisingly, however, quantum computing (seemingly the more difficult proposition) had a huge breakthrough last February, when Canadian startup D-Wave demonstrated the first commercial quantum computer. (It even played Sodoku.) Some academics were skeptical, but NASA's Jet Propulsion Laboratory verified D-Wave's claims, as JPL fabricated the quantum computing chips for D-Wave. So far this prototype is limited -- not even as fast as a normal desktop computer, and no doubt much more energy-intensive due to the cooling system needed for the superconductors -- but by the end of 2008 D-Wave hopes to have a model that is 64 times as powerful. Growth will no doubt continue from there.

Power Supplies and Monitors

Efficient CPUs are nice, but they're actually just one slice of the computer's power-consumption pie. Intel technologists writing a self-promotion piece (but a nicely technical and informative piece nonetheless) for Power Management Design Line included the following chart, which shows CPUs only drawing about 5 percent of a PC's total power.


I'm very skeptical of this, since measuring my own computer (a laptop) with a P3 International Kill-a-Watt Electricity Usage Monitor meter showed the power consumption roughly doubling when I'm maxing out the CPU compared to idling.

But there's no doubt that power supplies are as important for green computing as CPUs. Power supplies have been notoriously inefficient, and everything in the computer runs off of them: they turn the AC power from the wall into DC voltages that the various components need.

Monitors are also a large slice of the pie. LCD monitors (flat screen monitors) are vastly more efficient than CRTs (monitors with picture tubes); depending upon the model, LCDs can use 25 to 50 percent less power when active, as well as only one-tenth of the power of a CRT when sleeping. Also, while they do contain trace amounts of mercury, LCDs don't contain the lead found in CRTs.

With LCDs having largely replaced CRTs as the standard display for personal computers, there isn't that much difference in the market. But some LCDs are more efficient than others. Samsung offers an "ultra-efficient" model that exceeds the US Environmental Protection Agency's (US EPA) EnergyStar efficiency standard by 25 percent.

The next big thing in monitors will be reflective, daylight-readable displays like e-ink and IMOD (worth an article in its own right, for its biomimetic display technology). Already the One Laptop Per Child (OLPC) XO-1's monitor has a black-and-white reflective mode where power consumption goes down to 0.1 watt (compared to 8-10 watts for a normal laptop LCD)! This is an enormous leap that should be copied widely.

Until recently, most computers' power supplies have turned as much power into waste heat as they have into DC current for components. But the days of 50 percent efficient power converters are ending. The US EPA's 80 Plus program is a certification for power supplies; to earn it, the device must be at least 80 percent efficient and have a power factor of at least .9. The latest version of the EnergyStar certification requires products to be 80 Plus compliant.

Power Integrations may be the leader in efficient power supplies. For years this company has pushed the envelope for converters in several industries; not just computers and peripherals, but appliances and high-voltage applications as well. ON Semiconductor has also been a leader; it was the first company to open-source a design for an 80 Plus certified power supply. (Not unselfishly, however: the design required Power Integrations components.) The company have even created a laptop power supply design that is 90 percent efficient. Another mover is Marvell Semiconductor, which recently announced a new digital power factor corrector controller that may be a contender. The company hasn't released performance numbers, but claims that it replaces up to 20 separate components with one chip.

Greener Materials

The past two years have seen a radical shift in circuit board materials. Most companies have phased out once-ubiquitous lead solder; within two more years probably none at all will be using it. Unfortunately, however, this was not the result of enlightened self-interest; the industry had to be forced into it. The cornerstone to greener materials in electronic components is Restriction of Hazardous Substances (RoHS), the European Union law that bans cadmium, hexavalent chromium, lead, mercury, polybrominated biphenyls (PBBs), and polybrominated diphenyl ethers (PBDEs). Joel Makower has described RoHS as "the most significant transformation in the manufacturing sector since the banning of ozone-depleting substances in the late 1970's." Companies that ignore the legislation (or are not careful enough about vetting their supply chain) get smacked hard: Sony lost about $150 million when the EU banned its' PlayStation gaming console due to excessive cadmium content.

All the major electronic parts catalogs now label components as being RoHS-compliant or not, and third-party certifications now exist to thoroughly inspect supply chains. RoHS has changed not only circuit board materials but also plastic cases, for which PBDEs were the industry-standard flame retardant.

Other substances have come under scrutiny as well, most notably tantalum, an element used in many capacitors. Besides being extremely energy-intensive and waste-producing to mine, tantalum has been vilified for where it comes from: although most of the world's tantalum is produced in Australia, Canada and Brazil, a significant portion comes from the Congo, where as Wikipedia puts it, tantalum mining has "been implicated as a major source of income for the military occupation of Congo. To many, this raises ethical questions akin to those of conflict diamonds." Tantalum mining in the Congo also destroyed large swaths of habitat for already-endangered gorillas. This controversy was touched off by a 2001 article from the Industry Standard (reprinted here). Engineers can choose other capacitors to replace those containing tantalum, such as aluminum-electrolytic or ceramic. While these do not have equally good performance characteristics, clever system design can often eliminate the need for high-performance components.

[The tantalum issue initially became visible as a human rights and environmental issue under the rubric of coltan mining. According to Wikipedia, tantalum is one component of coltan ore. - Ed.]

In 2007, the EU took a new step that made RoHS look like training wheels, passing the the Registration, Evaluation and Authorization of Chemicals law (REACH). REACH requires all chemicals sold or used in Europe to be registered with the European Chemicals Agency, and requires manufacturers or distributors to supply materials safety data sheets, risk management guidelines, and safety measures for all usage scenarios. Many hazardous chemicals (over 1,500 of them) will require permission from the European Commission to use, and some chemicals will not be allowed at all. By far the the biggest impact of this law is that it institutes the "precautionary principle," which puts the burden of proof on companies to demonstrate that their materials are safe, rather than burdening the government with proving that they're harmful. Since REACH is still new, it is unclear what effects it will have in the electronics industry, but it will certainly create shifts -- not just in material use, but in the thinking processes of designers and engineers, as they learn about the health and environmental impacts of various chemicals they specify in their products.

The computer industry needs to get more proactive about material choices. Aside from a few small forays, like HP's PLA cased printer, or NEC's cell phone made with a PLA-kenaf composite case, almost nothing has changed. Lenovo now has a monitor which uses over 25 percent post-consumer recycled plastic; it is a great step forward, far ahead of the competition, but is still paltry compared to what should be done. If the industry keeps dragging its feet, the shift to green materials will continue to be driven by legislation, something that is rarely wise in corporate risk management strategies. Manufacturers need to take bold steps into the lead -- if not to change the world, than to stay in control of their own regulatory destinies.


Until computers are made from materials that are edible and nutritious, the best way to green the materials in computers is to simply use less of them. This is done by "dematerialization:" turning the product into a service by replacing individual computers with a system central servers accessed by distributed terminals. The best example of this continues to be Sun's Open Work Practice, which uses Sun Ray thin-clients. There hasn't been much news here, and there doesn't need to be: Sun Rays only use four watts of power (not including the monitor) and a fraction of the materials that go into a normal PC. (Sun doesn't list numbers, but the Sun Ray certainly cuts material use by half, and perhaps by over three-quarters, of the average PC.) What's more, Sun Rays last far longer than a normal computer, because they don't become obsolete; they are simply terminals through which the user accesses the server. And Sun provides a five-year warranty for Sun Rays while most computers now obsolesce in two years.

The best example of dematerialization for individual users is the Zonbu network computer. Like a Sun Ray, it has very little inside of it -- no hard drive, no CD or DVD drive, just a motherboard and a compact flash card (and enough ports for any peripherals you'd want). Unlike a Sun Ray, it runs applications locally, so it does need a decently fast processor and some memory, but it saves all files on the server. Zonbu also runs Open Office-based programs that are compatible with Word, Excel, etc.

However, when you factor in monitors as well, the winner in dematerialization will be OLPC's XO-1 mentioned above. The hardware design is excellent, and effectively pushes the market to see what is possible. Once released, the XO-1 will have a significant impact on the industry. (When I tested a beta version of the XO-1, the software was not yet ready for prime time, but presumably the project has been working on this.)

The Sum of Its Parts

What does all this information about components add up to, when you look at a whole computer? Stay tuned for next week's Green Computing Update, Part 3, where I look at the greenest computers on the market, and the greenest things to do with a computer when it gets old.

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Very very good article, great work !
I can't wait the part 3 ;-)

Posted by: Frederic on 17 Nov 07

Cool, I hadn't noticed this was up yet when I replied again to the last part.

Mention of VIA chips in the next piece?, Asus' bamboo-case laptop; I have a feeling that Power over Ethernet (and that usb can power all kinds of devices) is going to play a part in changes to how on-the-grid power delivery will occur.

Posted by: zupakomputer on 17 Nov 07

As someone deeply involved in this from the inside I can say that we are nowhere near "green" computing. Wait a few decades - we're taking baby steps driven by regulation right now. Once the electronics industry really understands what can be done it willmake this all look like greenwashing.

Oh, and lead won't be out of computers in two years, or in a decade. There are many applications where it's a necessary material. The EU is only going to recommend whether servers/infrastructure will be required to phase it out of solder, and the timeline for the restriction, in 2010. Lead's replacement, tin, has also been implicated in poor mining practices and funding of the military in Congo.

Posted by: Notahippie on 18 Nov 07

Quantum computers will be out way before a few decades.

Anyway - I want to know where I can buy these RoHS compliant products from, and recycled (etc) cases. I can find 80 Plus PSUs fine because their website lists all the PSUs that are certified. Can't find similar company or vendor or certifier sources of info for the other available products. USA seems to be way ahead with vendors listing such things, but import tariffs make that not-an-option for me (your prices however are waaaaay better than here).

Posted by: zupakomputer on 19 Nov 07

Saying that - where are there lists of what green IT companies I can apply to for work? They also must allow proper clothes to be worn. Am I dreading any interviews, I'm thinking I'll need to buy all new clothes.

Posted by: zupakomputer on 19 Nov 07

Zupacomputer, thanks for the reminder about VIA; I'd forgotten to check up on them. Looks like they're going strong, with their "Eden-N" processor running 500MHz at just 2.5 watts (!!!), and 1.5GHz at 7 watts! That's a tiny fraction of most CPUs. Press release here:

As for places to get RoHS components, the only one I've actually shopped at that lists RoHS compliance in the search-hits-list descriptions is Jameco (, but I'm sure other companies call it out in their catalogs as well.

Notahippie, thanks for the comments about lead and tin. Personally, I'm hoping for beter conductive organic polymers, things that can be inkjet-printed. I forgot to mention those in the article, but people are working on it for printing circuit boards.

Posted by: Jeremy Faludi on 20 Nov 07

By the way, Neoware ( ) is another thin-client computer that I forgot to mention--they're similar to the Sun Ray or Zonbu, but do laptop-style thin clients as well as desktops. They recently got acquired by HP, so hopefully they'll become more widely adopted.

Posted by: Jeremy Faludi on 22 Nov 07

Further correction on VIA:

Ben Hall from VIA wrote me after hearing about the article, and said:

"the VIA Eden-N is an older product; we now have a newer 500MHz x86 processor on the market that has a TDP of just 1W (and an idle power draw of only 0.1W)." Which is truly amazing.

He also pointed out that Zonbu computers use the VIA chip, and that PA Semi's chips are "focused on the embedded market, and not the desktop/laptop/client space."

So, clearly not enough credit given to VIA, apparently the real leader in performance-per-watt for CPUs.

Posted by: Jeremy Faludi on 23 Nov 07



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