Shopping around for a power supply on a tight budget can be a bit of an ordeal. On forums, everyone will have their own opinion of what constitutes a good power supply, and similarly to mechanical HDDs, a single bad experience can put a user off a brand forever. My golden rule, unless you need a specific feature/amperage on the power lines for unique GPUs, is to take the total power draw of your system and add 40%. My analogy is thus ? a car whose top speed is 80mph will squeak and rattle if you run it every day at 70mph, whereas a car whose top speed is 130mph will hum along nicely at 70mph. Others may disagree, but I find this is a nice guideline when building systems for family and friends.

Most desktop systems bought and sold today are often very basic, with integrated or a low end graphics card, making power requirements very low. However the extreme is also true, with users wanting to make the most out of three or four end GPUs with a heavy deal of overclocking. If you can recall our Gaming CPU article from April 2013 we used a 24-thread dual-processor system with four 7970 GPUs, lightly overclocked, which drew 1550W at load. This is why power supplies north of 1000W exist, and it can be very frustrating to get these units to be very efficient. To that end, Corsair is releasing today their AX1500i, a 1500W model certified with 80 Plus Titanium qualifications.