The Environmental Differential

Environmental considerations, as well as a slowing economy, have both consumers and companies enthusiastic about what some are calling a fad, and others, a necessity. The CRN Test Center decided to build a "green" PC—with some components supplied by several vendors and others by Harrisburg, Pa.-based D&H Distributing Ltd.—to see how the numbers add up.

We decided to focus our attention on the power consumption of the individual components used, as this is where the Test Center believes the interest of most SMBs will lie. As we were sourcing the parts, newer, low-power competitors were just being announced, and that trend is likely to continue. The components we used had the lowest draw, relative to their functionality, that we were aware of at the time of testing.

Motherboard
The motherboard we chose is the AsusTek Computer Inc. P5E3 Deluxe WiFi-AP @n. Billed as "The Most Energy Efficient Motherboard in the World" (a claim that another Taiwan-based board manufacturer is currently contesting in court), the heart of the P5E3 is the Asus EPU (Energy Processing Unit).

The EPU analyzes the CPU load and dynamically regulates various parameters to optimize power consumption. Asus states that the EPU, working together with its AI Gear 3+ utility, can attain power efficiency and energy savings of up to more than 58 percent.

This particular model of the P5E3 features Intel Corp.'s X38 chipset, which supports CrossFire (should it be used for gaming), includes a remote control and has passive cooling, as well as on-board WiFi 802.11n. In addition to the expected internal and external connections are two Gigabit RJ-45 ports that allow the PC to serve as a network gateway for managing traffic between two separate networks.

The first screen to appear when the board is powered on is the menu for the Asus Express Gate. Express Gate is an embedded, Linux-based, instant-on (approximately five seconds) environment that gives quick access to both the Web and Skype. The user can also choose to continue booting, enter the BIOS or power off. Express Gate will automatically exit and boot to the OS after a preselected amount of time. Because Express Gate is entirely self-contained on the motherboard, it can be used even when a hard drive isn't attached.

Since the P5E Deluxe does not have integrated graphics, we used the Radeon HD 3470 from Advanced Micro Devices Inc.'s ATI division. This high-definition card is built on 55nm technology that allows it to run cooler and quieter. It is designed with up to twice the processing performance per watt than previous generations of AMD GPUs and utilizes ATI's PowerPlay Technology to dynamically reduce power consumption at idle or low usage.

The HD 3470 is a PCI Express 2.0 card that has a DVI Dual-Link connector and an S-Video port. There also are CrossFireX connectors for the gamers. A large heat sink covers about 90 percent of the board with no fan.

Next: Chips, Storage And Power Chips, Storage And Power
Although a quad-core processor is likely the first choice most customers and DIY consumers would go for, a similarly priced, faster dual-core can actually be more power-efficient. The chip we used for this PC is the Intel Core 2 Duo E8500. The E8500 is one of Intel's latest 45nm Penryn dual-core processors. It is rated at 3.16GHz, with 6 MB of L2 Cache and a 1,333MHz Front Side bus.

Our system's storage device is the 500 GB Hitachi Global Storage Technologies Deskstar P7K500. For the moment, the P7K500 is considered the world's most energy-efficient desktop hard drive. Hitachi has implemented a set of power-saving technologies to reduce the P7K500's active and idle power consumption by up to 40 percent over the previous generation. With idle power utilization of 4.8 watts (3.6 watts on the 250 GB capacity model) and active power requirements of 8.2 watts (6.4 watts for the one-disk model), the P7K500 utilizes just over half of the idle power typically allotted to hard drives in Energy Star-rated PCs.

Although there are lower wattage power supplies available, we used the 850-watt Antec Inc. TruePower Quattro 850 (TPQ-850). This 80PLUS-certified PSU consumes about 33 percent less energy than many equivalent power supplies with the same power output. It has four 12V rails to increase stability by allowing the distribution of loads and sleeved, modular cables of various configurations to give a clean installation with better airflow.

The TPQ-850's fan rotates slowly and automatically speeds up as heat increases. In addition, it features Active PFC (Power Factor Correction), which alters the input current, thereby reducing electrical costs.

Designed to operate at a relatively lower voltage, it is now more feasible to use DDR3 memory in systems due to consistent reductions in price. These two reasons most likely contributed to Asus' decision to use DDR3 in the motherboard. Kingston Technology Corp. launched the 1,600MHz HyperX DDR3 midrange memory to complement their high frequency, top-performing products. We used a kit of two modules, 1 GB each.

In The End ...
What were the final numbers for our green PC?

Our standard test bed of an Intel DG33FB motherboard, containing the Intel Q6600 CPU, had a power draw of 85 watts at idle and max of 145 watts when running the full suite of tests in the Geekbench2 Benchmarking program, in which it achieved a score of 3,881. Our "green" PC had a similar idle draw of 83 watts, but a max of 105 watts when Asus' AI Gear 3+ utility was set for auto power savings. At this setting, it scored a 3,711 on Geekbench.

We found that the graphics card seemed to have a huge effect on the power consumption. Although there are cards that offer better performance-per-watt specs, if the performance is not needed, the excess energy usage is a waste. Changing the settings on AI Gear 3+ also allowed us to achieve much better power savings (83/95 watts), but at the expense of performance (Geekbench2 score 3,204).

The bottom line is that with careful component selection and a little tweaking, significant energy savings can be had that, multiplied by the number of units a company has, adds up to a significant—and measurable—ROI.