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All of these various developments dovetail nicely with the new voluntary computer specification for the US Environment Protection Agency's (EPA) Energy Star program that is coming into effect in 2007. SPCR published an extensive article on this development a year ago when it first came to light: A New Energy Star... in 2007.
Currently, the Energy Star specification for computers, integrated computers (such as the iMac) and monitors is not demanding. It only specifies what AC consumption should be while in sleep mode during which as much as 10% of the included PSU's power rating is allowed to be consumed. The proposed revision introduces power consumption targets while the computer is actually powered on and running. The latest draft of the revision, which has changed since the article linked above, was discussed at a stakeholder meeting hosted by the EPA on February 15, 2006 in Washington, D.C.
Here's a partial summary of the power requirements of the proposed Energy Star spec discussed at that meeting:
Summary of ENERGY STAR Program Requirements for Computers
Draft 1, version 4
1) Desktop / Multimedia Computers
Standby (Off Mode): < 2W
Sleep Mode: < 5W
Idle Mode -
--- Basic Performance*: < 49W
--- High Performance*: < 74W
2) Integrated Computer Systems
Standby (Off Mode): < 3W
Sleep Mode: < 5W
Idle Mode: TBD
3) Notebook Computers / Tablet PCs
Standby (Off Mode): < 1W
Sleep Mode: < 7W
Idle Mode: < 21W
Standby (Off Mode): < 2W
Sleep Mode: < 5W
Idle Mode: < 115W
5) Power Supplies
-- Internal: For all of the above system categories, if an internal power supply is used, it must have 80% minimum efficiency at 20%, 50%, and 100% of rated output and Power Factor of > 0.9 at 100% of rated output. This is identical to the 80 Plus certification requirements. The PF spec is only possible to meet with Active PF correction.
-- External: If an external PSU is used, then it must comply with Energy Star External Single Voltage AC-AC and AC-DC Power Supply Specification (>84% efficiency)
|*The desktop / multimedia PC category has been divided into basic and high performance. This was requested by the industry to reflect the huge range of PC performance in the marketplace. Currently, the definitions are simple: Any PC with dual processors, a multicore processor or a single-core processor clocked higher than 2.7 GHz is considered high performance. Single core or single processor machines with clock speed lower than 2.7 Ghz are considered basic performance. Obviously, these definitions need refinement, as admitted by Energy Star staff; they are starting points. The role of graphics cards needs to be accounted for, and CPU performance cannot be simply correlated to clock speed, especially when comparing different processor lines, even from the same company.
The 49W and 74W idle targets for desktop / multimedia computers are quite aggressive. There's no question that the vast majority of desktop computers sold today cannot meet the idle power limit of 49W AC for basic performance models. However, with some adjustments, including the use of a high efficiency power supply, most current MoDT PCs, and minimalist systems running AMD Cool'n'Quiet engaged processors without high power graphics cards could probably comply with this demanding low idle power requirement.
The proposed Energy Star computer spec is slated to go into effect on January 1, 2007, but there is talk of pressure from the industry to delay the date to July 1, in order to give all the players adequate time to get ready. It's rumored that Dell and HP already have prototype Energy Star models that comply with the desktop spec, and they want the additional time to try and obtain required components at minimal or no additional cost (compared with current non-compliant parts). The efficient power supply is likely the single most significant cost. Once the new spec comes into effect, it's likely that all US government agencies will be required to seek Energy Star compliant products for their IT purchases. Schools, hospitals and other enterprises are likely to follow suit for savings in energy cost. This represents a very sizable market.
Certainly, not all PCs will meet the new Energy Star spec. The EPA anticipates that some 25% of products will be compliant, compared to 98% of computer products with the current much less stringent spec. The Energy Star marque will then be meaningful for consumers of computer gear rather than just a ubiquitous rubber stamp. The marque will identify high energy efficiency computers. If the price difference is small, the typical consumer will choose an Energy Star PC over one that is not certified. Certainly, when the new Energy Star spec comes into effect, consumer awareness about energy efficiency in PCs will rise.
RUNAWAY GPU THERMALS
The realm of graphics cards and gaming PCs is truly horrid at this time, from the point of view of noise, thermals and energy efficiency. The problem is with graphics card makers ATI and nVidia, who have raised the thermal / power envelope of their top GPUs well beyond the 100W mark. With SLI and Crossfire, they have pushed the thermals beyond that of the hottest CPU. Two graphics cards each radiating in excess of 100W, just a few centimeters from each other ? there is little hope for such a setup to be even remotely quiet or energy efficient. Passive midrange cards are getting fewer and farther between, and worse, the tech press seems to encourage it. For every midrange or low-end graphics card roundup, there are a dozen unrealistic high end comparisons that worship the success of ATI / nVidia in setting some new record on some random benchmark.
This is not to dismiss the recent efforts of some brands in offering fairly high performance passively-cooled graphic cards. Asus has been very active in recent months, with a growing range of innovative, cleverly implemented passively cooled graphic cards. Gigabyte also has quite a range of passively cooled cards. There are many aftermarket passive and quiet heatsink mods from Zalman, Arctic Cooling, and Thermalright, to name just a few, and these products can help tame the noise of some graphics cards, but never the hottest and fastest. They cannot change the massive heat dissipation that's at the heart of the problem. A sign of the times is Sapphire's new Blizzard Radeon X1900XTX card, which utilizes a miniaturized liquid cooling system for quiet operation.
The future looks bright for quiet computers. Dramatically improved power efficiency in processors and power supplies, and a broad trend towards performance-per-watt as the key industry benchmark bodes well for improved thermals in computer gear. Extremely quiet off-the-shelf computers such as the new Core Duo powered iMacs will probably become more commonplace. In time, the average PC may become quiet enough for the average user. With increasing exposure to quieter machines, consumer awareness of PC acoustics is bound to rise, and demand for quieter computers will be greater than ever.
The trend towards quieter computers will be especially apparent in the entertainment PC arena. Entertainment PC technologies have finally matured and appear capable of delivering on their early promises. As computers move into living rooms and dens, consumers will increasingly demand low noise as a fundamental requirement.
We have not discussed the other main source of noise in PCs (other than fans), the hard drive. Suffice it to say that while the very quietest desktop HDD of four years ago was actually slightly quieter than the quietest desktop model available today, industry-wide adoption of the Fluid Dynamic Bearing has led to a dramatic lowering of HDD noise from all the manufacturers. Furthermore, a growing number of even quieter 2.5" notebook drives in ever higher capacity with desktop-compatible SATA interface has expanded options for quiet PC builders. (See the Storage section of SPCR for more details.)
There are other areas where improvements in power efficiency are needed. For example, the efficiency of most VRMs on motherboards plummets way below 80% when the CPU power demand drops down to the <20W levels required to meet the 49W idle power Energy Star spec. Actually, CPU power needs to be more like <10W, and VRM efficiency at that point is usually below 60%. As the industry responds to the challenge of Energy Star, we can probably expect specialized MoDT motherboards to improve VRM efficiency at low power levels. And even though there will probably quite a few PSUs that can meet the 80 Plus spec soon, we would welcome further improvements in power supply efficiency, perhaps approaching 90%, if it can be done without exorbitant cost.
One sometimes wonders if the GPU power race will ever stop, but it is salient to remember that Intel hit a wall with CPU clock speed increases and thermals. There's no reason to believe that GPUs can continue getting hotter indefinitely. Perhaps a move to multicore GPUs could trigger interest in higher efficiency. Perhaps the desire to obtain Energy Star approval will spark a change. It is also worth noting that extreme gaming machines are few and far in between, despite the marketing efforts of the graphics card makers and the obsession of gaming hardware review sites. The prohibitive cost of the hottest graphics cards is enough to keep them out of the reach of all but the most fanatical gamers.
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