Tom's Hardware > All Reviews > Components > Cooling > Stress Test: Power Supplies Under Full Load

Stress Test: Power Supplies Under Full Load

07:00 - Monday 11 July 2005 by Frank Völkel

What an epic project - 19 different power supplies were analyzed in our 6-week Live Stress Test conducted at the THG Lab in Munich, six of which did not pass the test. Maximum output ranged from 300 watts with the Fortron all the way up to 850 watts with the Turbo-Cool from PC Power & Cooling.

Looking at the comparison tests conducted over the last few years we see a substantial improvement in power supply quality and features. Users have to dig a good bit deeper in their wallets too however, as it takes an investment of about $150 for a good device in the 500 watt class, with nearly no ceiling in terms of product pricing. The top-of-the-line model in our field of test candidates, the Turbo-Cool 850 from PC Power & Cooling, is built for a maximum 850 watts and costs right around $500. Somewhat less shocking is the fact that for a short while now the market has offered an unprecedented variety of devices. This includes a host of no-name products in the lower price range promising extremely high performance for very little money. These types of offers were excluded from participation in our Stress Test.

And how do things work out in actual practice? Power supply buyers and shoppers are generally naïve, trusting manufacturer claims blindly. As our test however reveals, these maximum output specifications are problematic - even in the upper price ranges. The "500 watts" stated, referring to the combined performance of the individual cables, fails by a long shot to reflect actual performance. And for users it is nearly impossible to check these performance specifications. This is why numerous manufacturers do not hesitate to use exaggerated wattage specifications in promoting their products to trump similar claims by competitors.