Performance

Tested on: P4 3.0E @ 4.0 Ghz, 1.55V. ABIT Fatal1ty AA8XE, 1GB OCZ PC2-5400 EB, Radeon X850 XT, Maxtor DiamondMax 10 SATA.

All lines are fluctuating a bit, but nothing too serious. Considering the load we put on this small 300W PSU, it is suprising that it kept the system stable.
All lines are well within the limits set by the ATX Specification.



Above image shows the Ripple Voltage measurement (10 mV per vertical division, 0.1uS per horizontal division). With 20mV from peak to bottom it is nothing special. Ripple Voltage was measured at idle.


Standard deviation is a statistical term, which tells how far away from the average the measurements are. In other words it's the average of the average.
A large standard deviation indicates that the data points are far from the average and a small standard deviation indicates that they are close within the average.

Power Factor is a measurement of how efficient a power supply is converting AC voltage to DC voltage. The perfect power supply has a Power Factor of 1.0. Using Passivce or Active PFC increases the Power Factor. In the European Union all power supplies >70W must have either Passive or Active PFC.

As additional safeguard, the PSU is constantly monitoring all output lines, as soon as measured current draw exceeds a certain maximum, it will turn off:


What I noticed, is that even though the PSU is fanless, it emits some electric noise. During normal operation it is not noticable, but when you put your ear right on the PSU case, you can hear it.
Also when load is high, you can hear the sound coming out of your case. What is even more disturbing is that the tone constantly changes with the load, so you notice it much more, compared to a constant high pitched sound.

The lack of a backup cooling fan can be seen as good or bad.
It removes fan cost and adds more available space to the inside of the PSU. This allows the heatsinks to be bigger for more cooling performance.
On the other hand a fan might come in handy in some critical situation where overheating might happen.
However, we tried a few things to break the FSP ZEN but it always came out top.

Value and Conclusion