Inadequate and Deceptive Product Labeling: Comparison of 21 Power Supplies

Voltage Drop - Fixed-Voltage Regulators Under Load

Resistive power resistors (50 watts) are used to create the loads.

In addition to the maximum overall output, the stability of the +3.3V, +5V and +12V voltage ranges plays a key role. The combined output of the +3.3V and +5V ranges is important here, since the graphics card, the CD-ROM drive and the hard disks run on this supply voltage. The +12V channel is subjected to a heavy load by the processor, the motherboard and the CPU and graphic card coolers, plus case fans. Excessive voltage within the +12V circuit can damage the CPU if the longitudinal controller on the motherboard cannot equalize this. If it fails to do so, the die temperature of the CPU increases excessively.

Due to the absence of a heat protection facility on AMD Athlon XP processors, a dangerous situation can arise if the motherboard’s protective circuit does not function reliably. Precise details on the combined output of the three different voltage ranges (3.3, 5 and 12-Volt) are not specified by all power supply manufacturers. The Enermax and Antec stand out from the crowd with their good documentation of these figures. Manufacturers’ specifications are an important source of information, at AMD and Intel, upon which this comparison test is based.

Silent : the fan of the Verax power supply is motionless, although it is, in fact, working. The fan does not kick in until the load is higher.