OCZ GameXStream 850w ATX PSU
Published: 17th November 2006 | Source: OCZ | Price: |Load Testing
In order for the results from all current and future PSU reviews to remain fair and comparable, Overclock3D uses a custom built Power Supply load stress tester. The tester will be placing the following loads on each of the GameXStream's rails:
+3.3v - 20a Load
+5.0v - 20a Load
+12v1 - 15a Load
+12v2 - 15a Load
+12v3 - 15a Load
+12v4 - 15a Load
The results are collected from a Mastech MAS-345 Multimeter which logs its readings via RS232 to a PC.
Efficiency tests are performed by measuring the wattage consumed by the power supply at the mains against the power (in watts) consumed by the OC3D power supply stress tester. These results may not be 100% accurate, but have proven to be extremely close to results obtained from professional equipment.
Possibly the hardest part of any PSU review is summarising the level of noise given out by the unit. The threshold for what is considered 'noisy' varies from person to person and therefore what I may consider a quiet unit, another person may consider extremely loud. A common way to resolve this issue is to use a dBA meter to measure the units noise level, however this doesn't take into account the pitch (type) of noise emitted and whether it is likely to irritate end users.
For this reason OC3D records all power supplies at idle and load in wav format for you to make your own informed decisions. All recordings are taken at 30cm away from the PSU and outside of a PC case. You will need to remember that noise levels will be reduced by varying amounts once the PSU has been installed inside your PC enclosure.
Idle Recording - Download
Load Recording - Download
I was pleasantly surprised by the low noise levels emitted by the GameXStream both at idle and under load. Most high wattage power supplies seem to have trouble maintaining low noise levels when under full load, however the GameXStream managed this effortlessly.