Lowering PC Costs

Component manufacturers continue to increase their emphasis on becoming green, and are producing products that perform as well as, or in some cases better than, older models, while drawing less power. By using these components to build a new PC, or substituting just a few in an aging one, energy use can be considerably reduced.

During our tests, the one component that had one of the most significant effects on power consumption was the graphics card.

When it comes to controlling the power draw of your video card, the first rule of thumb is to determine what the system will be used for. Aside from the higher electrical drain faster graphics processors have, they also generate much more heat, which requires more energy for cooling. For a computer that isn't going to be playing the latest in video games, a high-end graphics card is overkill. Using a less powerful GPU also will lower the cost.

Gamers aren't out of luck though. Cards, such as the just-released AsusTek Matrix ENGTX260, are designed for overclocking and, as such, have adjustable voltage regulators. While this feature is primarily used to increase the voltage while boosting the speed of the GPU, it can just as easily lower the voltage when the system is being used for less graphic-intensive jobs.

According to a 2008 IDC report, power efficiencies, controllers, fans, etc., equate to approximately 1 watt lost for each HDD watt. In addition, it takes 1 watt to cool 1 watt. That means that a typical hard drive, specified to draw 12 watts, is actually responsible for consuming 48 watts at the outlet -- four times the drive's usage. By means of various technologies, hard drive manufacturers have been hard at work lowering the power draw of their products.

One such drive is Hitachi Global Storage Technologies' Deskstar P7K500. Hitachi has implemented a set of power-saving technologies to reduce the P7K500's active and idle power consumption. 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.

Western Digital's contribution is the GreenPower Technology line, including the Caviar Green models for desktop use. These drives include multiple features from improved spin-and-seek speeds, transfer rates and caching optimization to platter stability and vibration reduction, which result in an average power savings of 4 to 5 watts per drive.

When it comes to processors, similar to the graphics card, taking the computer's planned function into consideration can help avoid overkill. If the end user of the computer is not going to be doing any tasks requiring a quad-core CPU, a processor such as any in Intel's Core 2 Duo line may be satisfactory.

Specifically designed for energy efficiency, the Core 2 Duo has two cores built on 45nm technology, up to 6 MB of shared L2 cache and up to 1,333MHz front side bus. Although obviously not as powerful as the newer quads, we find them to be extremely versatile. And if you put some of the cost savings into adding more memory, the loss in performance would appear negligible to the typical user.

Simply by means of their function, you cannot really lower a PSU's consumption without lowering the amount of power it supplies. Most modern-day PSUs incorporate features to make them as energy-efficient as possible, thereby allowing you to consider using a lower wattage unit.

An 80 PLUS-certified PSU must be 80 percent or greater energy-efficient at 20 percent, 50 percent and 100 percent of rated load with a true power factor of 0.9 or greater. This makes an 80 PLUS-certified power supply substantially more efficient than typical power supplies.

Antec bills its EarthWatts PSUs as "One of the most environmentally friendly power supplies available." All 80 PLUS-certified EarthWatts power supplies also feature Active PFC (Power Factor Correction), which alters the input current, thereby reducing electrical costs.

For users whose requirements go above the highest 750-watt EarthWatts model, Antec's TruePower Quattro power supplies offer 850- and 1,000-watt units that incorporate many of the same energy-efficient features of EarthWatts PSUs.

Whether building a new system, or fine-tuning an existing one, with careful component selection and a little tweaking, significant energy savings can be realized.

Tweet

   

More Components & Peripherals