Since we don’t currently have access to an ATE load tester, a multi-meter is used to show each of the power supplies performance on the 3.3v, 5v and 12v rails. Although we can’t do full load tests, we can provide relative information regarding variance and fluctuation of current and ripple on the rails which is integral and indicative of quality in a power supply.
To perform the above tests, the methodology will be as follows:
I7 4770k @ 4.8GHz
Gigabyte Z97 SOC Force
1 x Zotac GTX 780
8GB (2x4GB) TeamGroup Vulcan 8GB (2x4GB) 2400MHz
1 x 250GB Samsung 840 EVO
Thermaltake Toughpower Grand 850w
Voltages will be monitored via a multi-meter and the AC power draw will be monitored via a power monitor when drew from the wall. For the idle test, the system will be simply booted up and let to run into windows and after 5 minutes when the power draw has leveled out, the readings will be taken.
To load and apply power to the power supply, a combination of IBT and Furmark will be run to put as much strain on the power supply as possible. After 10 minutes the readings will be taken and to ensure maximum strain, the CPU will be overclocked to 4.5GHz. Depending on the power of the power supply, multiple graphics cards could be used in line with how comfortable I feel the power supply will cope with such load.
ATX themselves specify that a fluctuation and variable of 5% is acceptable so to number crunch it means that:
3.3V = 3.135V-3.465V is acceptable
5V = 4.75V-5.25V is acceptable
12V = 11.4V – 12.6V is acceptable.
Any readings outside of these figures will be an automatic fail.
Total idle power draw =124 w which equates to just over 14.5% so it should do spot on within the efficiency states with such a low load.
Total loaded power draw =591 w which equates to just over 69.5% so there plenty of load to test the power suppliers efficiency. The results of the tests were as follows:
|3.3V = 3.18v|
|5V = 5.21v|
|12V = 12.34v|
|3.3V = 3.17v|
|5V = 4.98v|
|12V = 11.9v|
Our multi-meter put out more than acceptable results for a power supply of this calibre and specification; pretty much what I expected. the 3.3v line was probably the most abhorrent out of the three and was very close to the limits on both occasions but a strong showing in the 5v and 12v lines make up for that somewhat. Overall the performance is good and the fan does a good job at keeping the noise down; a big plus in my book.