Green computing, just as all things environmentally responsible, has taken off in the past few years. Consumers are paying more attention to the impact their PC purchases have on the world around them. They're opting for LCDs over power-hungry CRTs, choosing Energy Star-compliant power supplies, and picking up "green" hard drives with low power consumption. While certainly commendable, these products tend to focus on energy while ignoring the bigger picture — reducing waste, avoiding the use of harmful chemicals, and so on. First, one must understand that there's no silver bullet for the wastefulness of the computing industry — that Moore chap really nailed it. A computer will need to be replaced at some point solely because it will no longer be able to run the current software. By making smart decisions when building your next system, you'll be able to lengthen your computer's lifespan while reducing its overall environmental footprint. CPU/Motherboard While traditional dual-core desktop CPUs draw less and less power each year, mobile processors have always been designed with efficiency in mind. Due to size and cooling restrictions, mobile CPUs run cooler and consume up to 50% less power than their desktop brethren. While processors are plentiful, sadly only a few Mobile on Desktop (MoDT), as the genre is sometimes referred to, motherboards are available. Of the handful on the market, the majority takes advantage of the rarely-used Mini-ITX form factor. Primarily designed for use in home theater PCs or wherever fanless operation is required, these boards draw less power than their ATX and microATX counterparts and are much smaller physically. That means less resources go into the construction of each board, and less space is taken up when these ultimately end up in the landfill. While scouting out motherboards, look for Socket M and Socket P options from manufacturers such as AOpen and abit. MoDT motherboards from these companies feature desirable specs like Gigabit Ethernet, 7.1-channel audio, and either DVI or HDMI output. Additionally, both companies offer RoHS-compliant options for MoDT motherboards. RoHS, an EU directive for the restriction of hazardous substances, mandates that the levels of lead, cadmium, and mercury are kept to below 1,000 parts per million. (These toxic metals are common contaminants found at PC component disposal sites.) One of the best we've found is the miniscule AOpen i965GMt-LA Mini-ITX Socket P Motherboard (around $270 on PriceGrabber). It supports most Intel Merom and Penryn mobile CPUs and features an integrated Intel GMA X3100 video card with DVI-I output, Gigabit Ethernet, 7.1-channel audio, and two Serial ATA 3.0Gb/s connectors — the beginnings of a quality system. When it comes to choosing a CPU, splurge for a mobile Intel Core 2 Duo processor — perhaps one of the new "Penryn" models. With speeds of up to 2.6GHz at the moment, it should pack the processing muscle necessary for years to come. Some lower-cost Penryn CPUs: Intel Core 2 Duo T8100 2.1GHz Socket P Processor, model no. BX80577T8100, for $209 + $5.99 s&h at newegg.com Intel Core 2 Duo T8300 2.4GHz Socket P Processor, model no. BX80577T8300, for $250 + $5.99 s&h at newegg.com VIA's C7 processor is another option — while its solo-core architecture makes it a poor choice for more processor-intensive applications, it's downright miserly when it comes to energy draw. Case/Power Supply Power supplies were one of the first components to go green. While early PSUs boasted Energy Star-compliance, the new kid on the block is the 80 PLUS standard. 80 PLUS calls for a minimum of 80% efficiency, which greatly reduces the heat generated — and thusly power wasted — by a power supply. What that means is that, for instance, a 300-watt power supply running at its maximum load would be outputting 240 watts of power, with 60 watts lost as dissipated heat. A higher efficiency rating means that the PSU not only draws less power from the wall, but also that it needs less cooling to keep it running smoothly. One of our favorites is the SeaSonic Eco Power 300 300-watt ATX Power Supply — not only is it 80 PLUS- and RoHS-compliant, but its minimal packaging is made from 100% recycled cardboard. As for a case, choose the smallest one that fits your expansion needs. If you're just building a basic machine, or you're unlikely to use expansion slots for adding a video card or other upgrades, choose the smallest enclosure you can find. Many Mini-ITX and microATX cases measure under one cubic foot, resulting in less consumer waste. Additionally, look for a case made of aluminum, steering away from plastic cases and those with acrylic windows. Once it's time for a new system, you'll easily be able to recycle it in most locales. Although cases made entirely of wood are available, they're still a novelty (read: big bucks) and their usage is questionable. (Could these possibly meet FCC regulations on RF radiation?) For a green-ish case, we'd suggest the Thermaltake LanBox VF1000BNS. Its steel and aluminum construction bundled with a small form factor and the ability to work with both mATX and Mini-ITX motherboards makes it one of our favorites. It's not geared to the green market per se — you'll find plenty of styrofoam in its packaging — but it's well ventilated and provides just enough room for expansion without being overly large. Hard Drives With companies like Western Digital getting in on the green trend — it recently launched its GreenPower family of desktop hard drives — it's getting easier and easier to find green storage options. See our archives for recent Western Digital GP hard drive deals. WD's GreenPower drives sip 4-5 watts less than their standard counterparts, but there's a technology out there that's even more efficient — solid state drives (SSD). While these GreenPower drives are rated to read/write at 6 watts (under 1 watt for standby), SSD drives from companies like SanDisk and Samsung feature read/write power consumption of less than 1/2 watt, and standby at 1/4 watt. Although several times the cost of their platter-based ilk and much smaller in capacity, an SSD offers lower power consumption, faster booting and read/write speeds, and reduced heat dissipation. (Note: Most SSDs are 1.8" and 2.5" drives intended for use in laptops and will require adapters for use in desktop systems.) Video Cards, RAM, etc. Video cards, RAM, and other internal components have yet to really hop onto the green bandwagon. Ideally, one would utilize a motherboard with on-board graphics, but that's not always an option. If you have to use a video card, choose the one that's powerful enough for any applications that you're likely to run — you don't need an expensive &mdash and power hungry &mdash 9 Series GeForce card if you're only going to be watching YouTube on a 15" LCD. As for RAM, choose the largest and fastest single stick of memory you can buy. DDR3 SDRAM DIMMs consume less power than its DDR2 and DDR counterparts. Additionally, with more RAM, your system will have to rely less on virtual memory, allowing your hard drive to remain in its idle state longer and draw less power. Peripherals & Accessories As one would imagine, the number of peripherals used is proportional to the amount of energy used and materials consumed. Making smart decisions on what you'll need will lead to a overall greener experience. For a mouse, choose a wired model, which eliminates the battery found in wireless mice. While the switch to NiMH and Li-Ion batteries has been better for the environment, these batteries still leach toxins into water supplies when exposed of improperly. When choosing a keyboard, look for those made from aluminum, such as Apple's new Wired Keyboard — it's ultra-thin aluminum housing is recyclable, not to mention gorgeous. For displays, the industry-wide switch to LCD panels instead of power-gobbling CRTs has already done a lot to curb e-waste and power consumption. The best advice when shopping for a monitor would be to choose the smallest one you'll be happy with — not everyone needs a 30" computer monitor — and to look for the Energy Star rating. We like the Energy Star 4.0-, RoHS-, and EPEAT Gold-compliant NEC LCD195VX+BK 19" LCD Monitor. It draws only 37 watts at maximum usage and features a thinner bezel than most other displays. (Click here for more information on EPEAT, an environmental performance rating often referred to as a the "Green Computing Standard".) Jeffrey Contray is dealnews' Managing Editor.