Stability Power 450~500W

This power supply is as generic as can be, dull grey color, one specification label for all different models, ranging from 300 to 550W.

There are not a lot of connectors on this PSU, hardly enough to power a very low end system, don’t try to use for a new Intel or AMD system though, there’s no 8-pin power connector or 6-pin PCIe. This unit is for Pentium 4 and Athlon XP…



The all in one label shows maximum loads for each volt rail:

+3.3v: 28A

+5v: 38A

+12v: 20A

-12v: 0.8A

+5VSB: 2A

Older generation system did get CPU power from the 5v line, this explains the overpowered +5v and the underpowered +12v.



Our first test is loading the PSU up to almost 50% of rated capacity:



The efficiency is respectable at 77%, the voltage lines remain quite stable too, not too much deviation seen. The power factor is low, 0.57 (57%), most brand name units hit 90%+ numbers with ease.

Let’s try for close to 75% load:



Efficiency drops noticeably; to be able to output 361W we are drawing 533W at the wall outlet. The 12v rail drops quite low, while the -12v is up, clear signs of instability.

Do we dare to increase further? We didn't quite reach 100% load.



We increase the load on the 3.3v and 5v rails, the outcome is bad, quite bad, efficiency drops to 66% and we’re at the maximum of what this unit can take, after 5min we heard a buzzing noise followed by a loud pop and visible smoke, the Stability Power was dead. The numbers you see above are far from encouraging, the -12v line is way up, and while this unit is rated for 450~500W it doesn’t even come close to reaching 400W.



One dead, one to go, will the Sweex survive the tests ?