Everyone wants a high-end system, right? Unfortunately, they require tons of power to run, and those systems are consuming more and more energy, thereby increasing the need for things such as coal-derived electricity and fossil fuels. Owners of such systems are also spending a large amount of money per year (which they don’t need to do), and contributing to the global warming phenomenon (which definitely no-one needs to do). So, what if we could save on those energy bills and the planet at the same time? Is there such an option? Yes, by investing in a decent, high-quality PSU.

Anyone want to guess how much power this monster rig would waste on a PSU with a low efficiency?

Anyone want to guess how much power this monster rig would waste on a PSU with a low efficiency?

PSUs are, for the most part, the component we give the least amount of thought to. We buy one that will cover our system’s needs, or that comes bundled with our chassis, and that’s it – we don’t think about it again until it breaks. However, let’s take the average 500w PSU, for example. Let’s say it has 70% efficiency, which is decent for most models. If you max it out to its rated output, your system will run fine and will consume 500 watts of power, but what you don’t see is the power lost by the PSU.

Running at full tilt, it consumes a total of 714 watts from the wall socket. This excess energy is lost as heat, which the PSU expels as hot air. An extra 214 watts is big. Try running that system for an hour a day at full tilt: the PSU consumes, and you pay for, an extra 78,110 kilowatts a year – money that could be better spent on other things.

If we take a higher-end PSU that runs at 80% efficiency, we only waste 125w. Some models even run at 85%, which makes the wastage even smaller at 88w. The benefits of this are many-fold: not only are you saving money, but you’re lowering your entire system’s operating temperature, and at the same time reducing the need for more electricity to be generated to feed your beast.

Efficiency isn’t the only factor: capacitor ageing has to be taken into account as well. If your budget PSU has capacitors that lose 20% efficiency over 2 years, guess what? Your PSU loses as much as 40% efficiency overall, and wastes more and more power as it gets older. When selecting your PSU, not only do you have to take your system requirements into account, but also its power efficiency and the quality of the capacitors inside.

The Vantec Ion2+ 600W: easily one of the cheapest 80Plus-certified PSUs around.

The Vantec Ion2+ 600W: easily one of the cheapest 80Plus-certified PSUs around.

For peace of mind, I recommend that you first assess what wattage your system will consume using an online PSU calculator, and then add an extra 150 watts headroom. A PSU works more efficiently when it’s under less load, and by exploiting this you can bring your system closer to the 80% efficiency mark. As an example, a quad-core Intel with 4GB RAM and a GTX260 should consume under 500w from the wall. By selecting something like the Vantec ioN2+A van-550A 600w, you extend the PSU’s lifespan and save electricity in the process by maximizing its efficiency at those lower levels.