Obtaining Replacement Units

Most of the time, it is simply easier, safer, or less expensive (considering the time and materials involved) to replace the power supply than to repair it. As mentioned earlier, replacement power supplies are available from many manufacturers. Before you can shop for a supplier, however, you should consider other purchasing factors.

Deciding on a Power Supply

When you are shopping for a new power supply, you should take several factors into account. First, consider the power supply's shape, or form factor. Power supply form factors can differ in their physical sizes, shapes, screw-hole positions, connector types, and fan locations. When ordering a replacement supply, you need to know which form factor your system requires.

Some systems use proprietary power supply designs, which makes replacement more difficult. If a system uses one of the industry-standard form factor power supplies, replacement units with a variety of output levels and performance are available from hundreds of vendors. An unfortunate user of a system with a nonstandard form factor supply does not have this kind of choice and must get a replacement from the original manufacturer of the systemand usually must pay a much higher price for the unit. Although you can find high-quality, industry-standard form factor supplies for less than $50, the proprietary units from some manufacturers cost as much as $400 or more. PC buyers often overlook this and discover too late the consequences of having nonstandard components in a system.

See "Power Supply Form Factors," p. 1148.

Name-brand systems on both the low and high end of the price scale are notorious for using proprietary form factor power supplies. For example, Dell has been using proprietary supplies in many of its systems. Be sure you consider this if you intend to own or use these types of systems out of warranty or plan significant upgrades during the life of the system. Personally, I always insist on systems that use industry-standard power supplies, such as the ATX12V form factor supply found in most systems today.

Sources for Replacement Power Supplies

Because one of the most failure-prone items in PC systems is the power supply, I am often asked to recommend a replacement. Literally hundreds of companies manufacture PC power supplies, and I certainly have not tested them all. I can, however, recommend some companies whose products I have come to know and trust.

Although other high-quality manufacturers exist, at this time I recommend power supplies from PC Power and Cooling and Antec.

PC Power and Cooling has a complete line of power supplies for PC systems. It makes supplies in most of the standard PC form factors used today. Versions are available in a variety of quality and output levels, from inexpensive replacements to very high-quality, high-output models with ratings of up to 1,000 watts or more. It even makes versions with high-volume, low-speed (quiet) fan assemblies. Its quiet models are especially welcome to people who work in quiet homes or offices and are annoyed by the fan noise some power supplies emanate. My favorite models are PC Power and Cooling's Silencer 470 ATX for building quieter systems, Turbo-Cool 510 Express for systems that need the optional PCI Express x16 power connectors, and the Turbo-Cool 1KW (rated at 1,000 watts, it's one of the most powerful power supplies on the market).

Tip

PC Power and Cooling has SFX-style supplies that can be used to upgrade small form factor systems, including E-machines, HP's 67xx series, and others. If you have one of these systems and need a high-quality replacement supply to support your upgrades, PC Power and Cooling can help.

PC Power and Cooling also has units available that fit some of Dell's proprietary designs produced between 1996 and 2000. These units cost less than Dell's, are available with significantly higher output ratings, and bolt in as direct replacements.

Antec, Inc., also offers high-quality power supplies, particularly its TruePower series. It also offers power supplies that can operate with no internal fan, resulting in the quietest design possible. It even has some power supplies with internal lighting for interesting visual effects when installed in windowed cases.

A high-quality power supply from either of these vendors can be one of the best cures for intermittent system problems and can go a long way toward ensuring trouble-free operation in the future.

Power Supply Tips and Recommendations

With backward compatibility ensuring that the new 24-pin ATX power connector will plug in to older 20-pin motherboard sockets, when purchasing a new power supply I now recommend only those units that include 24-pin main power connectors, which are usually sold as ATX12V 2.x or PCI Express models. For the most flexible and future-proof supply, also ensure that the power supply includes a 6-pin PCI Express graphics connector as well as integrated SATA drive power connectors. An example of a highly rated power supply incorporating all these features is the Turbo-Cool 510 Express/SLI from PC Power and Cooling (www.pcpowercooling.com). Choosing a power supply with these features provides flexibility that allows it to work not only in newer systems, but also in virtually all older ATX systemsand with no adapters required.

See "ATX12V 2.x 24-pin Main Power Connector," p. 1178.