What PSU do I need?
Your power supply will be a large determining factor in the lifespan and performance of your computer system. The type of computer you are building will almost choose the kind of power supply you'll be buying. If you're creating a home or office PC, you won't need a very expensive PSU, and will likely be able to buy low price power supply that has power connectors for 20+4 motherboard connection, ATX12V 4-pin CPU power connection, SATA, Molex, and possibly a floppy disk drive(FDD). These are standard connections, and will be found in different number across various models. If you're building a gamer PC, you'll probably need the EPS12V 8-pin CPU connection, and definitely will need PCI-Express 6-pin or 6+8-pin power connections as well as the others mentioned. Other power supply features to look for when building a gamer or enthusiast level build are whether it's 80PLUS Certified and if it is has modular cabling.

What is modular cabling?
Power supply cables can take up a lot of room in your computer case. Modular cables allow you to connect just the power cables that you need to your power supply to use less cables and have easier cable management. Often, modular cables will have a woven sheathing for durability, and which also helps with cable management and air flow.

What does 80 PLUS Certified Mean?
The 80 PLUS Certification requires power supplies in computers and servers to be 80% or higher energy efficient of their rated load with a true power factor of 0.9 or greater. 80 PLUS certified means the supply is more efficient than a typical power supply and allow your system to run with higher stability. These are highly recommended if you're building a system for gaming or media editing.

What PSU should I buy for a gaming build?
We recommend power supplies that are 600 Watts or higher for gaming builds, meaning you'll have plenty of power for you video card and core components. These PSUs are able to support high-end motherboards and processors, as well as multiple graphics cards / other hardware. If you want to put a system together without spending a lot of money, then you'll probably want to get an uncertified power supply that you'll be able to install quickly and replace easily if it quits on you. The downside would be if it damaged your other hardware when it went out. To avoid that kind of situation, we've got 80PLUS certified power supplies with and without modular cabling to not only provide cleaner power, but better cable management for your system.

What power connector(s) do I need for my PC?

You'll need 6-pin and 6+2-pin PCI-Express power connectors for video card support. Some Video cards require both a 6-pin and a 6+3pin power connector. Motherboards require 20-pin or 20+4 pin connectors or their main power, and then either 4-pin ATX12V or EPS12V 4+4 pin connectors for the CPU power. Other power connectors are 5-pin SATA, 5-pin Floppy Disk Drive, and 4-pin Molex. Be aware of your connectors and what the hardware compatibility is before you make your purchases. On most modern motherboards the processor requires additional power so there's also the 8-pin EPS 12V connector - which is basically 2 x 4-pin EPS12V's. Most mid to high-end power supplies have this but some of the lower end models do not. Be very careful to check this before proceeding with a PSU.

Do lower wattage PSUs run cooler than higher wattage models?

There is no set rule for this, but in practice you'll see this is generally true. While it's always best to look at the specifications of the model of PSU you're looking at, you may find that low-wattage units output less heat and thus are better choices in small form factor cases and situations where heat build-up can be a concern.

What are the most common power supplies for desktops?

Most desktops use ATX power supplies in the range of 400 Watts to 600 Watts. These power supplies are generally thought to be 'Mid-Range' and depending on yoru build are the sweet spot of price & performance.

What power supply do we recommend?

We recommend power supplies over 600 watts for gamer builds, between 350w to 550w for most standard desktops and mid-range systems, and PSUs 300 Watts and under for HTPC / small form factor builds & replacements in existing systems. There are several tips you can keep in mind when shopping for an atx power supply - 1) always plan for at least 20% more capacity in your supply to handle future upgrades & modifications, 2) the higher the wattage usually means the more cooling necessary = the higher the noise, 3) spend at least 10% of your build budget on your PSU to ensure that you get a good quality unit that will last and won't harm your components.