OCZ StealthXStream 600 Watt PSU
Published: 11th October 2007 | Source: OCZ Technology | Price: |Load Testing
Each power supply that passes through Overclock3D is put through its paces with a custom built load testing device. Using this device, the PSU is subjected to various loads and the performance measured. This gives a much better idea of performance levels than methods employed elsewhere.
Furthermore, during testing, the power supply's efficiency is tested by measuring the power being drawn from the mains supply.
Efficiency tests are performed by measuring the wattage consumed by the power supply at the mains (Mains Draw) against the power consumed by the OC3D power supply stress tester (PSU Load). These results may not be 100% accurate, but have proven to be extremely close to results obtained from professional equipment.
In the graph above it is clear to see how well the StealthXStream handled increased loads with its Active Power Factor Control, doing a very good job of keeping the 12v and 3.3v rails up to ATX specification even at 100% load. The 5v however does appear to suffer at high load, however this is still well within the ±5% allowed on the +5v of the ATX form factor and so really is nothing to worry about.
On the specifications list for the StealthXStream, an efficiency of 83% @ 230v is claimed. As you can see above this has proved to be a pretty accurate claim, managing 82.77% efficiency at a load level most gaming setups could easily reach during stress. While 83% is nothing spectacular it is certainly up there with some of the best units we have seen at OC3D.
In our continuing efforts to make power supply reviews more thorough, rather than simply checking voltage stability, Overclock3D will now be recording the temperature of each PSU as it undergoes testing. Temperature recordings will be taken from the underside of the PSU's outer casing at 0%, 50% and 100% load levels using a laser infrared thermometer in an attempt to gauge how much heat is likely to radiate into the end-users case.
A particularly hard part of reviewing a power supply is giving an accurate indication of the noise generated by the fan and electrical components. The normal procedure at Overclock3D has become to record the noise given off by the unit with a high quality microphone, to give a relatively fair representation of the pitch emitted. Unfortunately the usual equipment for this testing is not currently available so you will have to take my word for it when I say that this power supply is extremely quiet. I like my silence and I am certainly very easily irritated, but I can happily say that the pitch of the fan did not come close to annoying and the level of noise, even at high load was tolerable.
Let's head over to the conclusion page to see how the StealthXStream performed as a whole...