Inadequate and Deceptive Product Labeling: Comparison of 21 Power Supplies

With its generous maximum output of 390 watts (at which point it powers down in an orderly fashion), the Verax FSP300-60ATV is an impressive performer. Thanks to its quiet fan, the Verax is practically inaudible in use. Also recommended is the Fortron FSP. This model achieved a maximum output of 450 watts - and it was quiet. The Herolchi HEC-300LR-PT was one of the least expensive units in our test. Despite its low price of about $50, this 300-watt power supply performed well. It also addressed safety issues adequately with a built-in safety cutout.

For those looking for a more readily available solution, we recommend the Antec True Power 380P. Antec has done a good job in making their products available from a variety of sources including many local retailers. Chances are that you will have no problems being able to find the Ture Power 380P. The True Power 380P offers a good balance of performance for the money, but expect to pay a little more for this unit, but you will get excellent packaging and a manual that is ahead of the others.

To Sum Up : More Support For Consumers

Our comparative power supply test indicates, beyond question, that some manufacturers need to make serious quality and accuracy improvements in the information provided with their products and with the performance statistics claimed in order to make these products perform as represented. Time and time again, our lab measurements were unable to verify the output figures represented on the model identification sticker. And how, exactly, is a computer purchaser supposed to check the output of a power supply ? This kind of feature marketing is not possible with other hardware components, such as processors or graphics chips, because the user can check for performance using benchmark-testing software.

Here are some of the salient facts from our lab test. The 520-watt rating of the Maxtron TOP520P4 was overly optimistic. In our test, it burned out well before this, when it reached a combined load of 446 watts. The Leadman LP-6100E also performed well below its manufacturer’s specification ; the specification claimed a 500-watt rating, but in practice it only delivered 426 watts. On the other hand, the power supplies from Conrad, TSP and Verax were able to provide stable voltages, even when stressed in excess of their specification. With a measured peak output of 454 watts, the Fortron FSP exceeded its specification by 23%. The 300-watt Verax was able to deliver an astonishing 390 watts.

Symbolic representation - Power supplies might not catch fire, but you can certainly burn them out.

We do not recommend the models we tested from Noise Magic, PC-World and Maxtron, as none of these models offer any safety overload protection (auto cutout) and their capacitors explode with an audible "bang !" well short of their maximum rated output.

There are a few surprises for the potential power supply customer in the area of price. With the exception of the SCS, retailing at approximately $30, all of the other test models retail for at least $50. The highest priced example is from Engelking, with its 300-watt model retailing at about $235.

Part of the test rig for checking the maximum output of a power supply.UPDATE : Investigation With Noise Magic

Following the review of power supplies our editors investigated with "A Conto Noise Magic GmbH" the failure of their test sample. It turned out that the NMT2-Enermax/350W-N/2GL is a 350 W model. However, the manufacturer limited the permanent power load to 250 watts due to air ventilation reasons. At a permanent load of 250 watts the power supply runs stable. The conclusions of the review at a load of 350 watts and the resulting failure of the sample are invalid, as the power supply is not designed for this load. However, the end user cannot gather this information from the label, which states 350 watts. The only reference of a maximum load of 250 watts can be found in the manual or on the website of the vendor. Furthermore, the manual contains recommendations for setup and operation of the power supply. The manufacturer will change the technical data on the label. In addition to the statement mentioned above the manufacturer would like to inform you that Noise Magic has power supplies in their portfolio that have better cooling and more power load headroom such as a 350 watts model.