Ultra X3 800W Modular Power Supply

Using CPUID’s HWMonitor, I took a snapshot of my system’s electricity usage.  I’m going to tax the crap out of my system by using Stressprime Ortho to give my RAM and CPU a little workout while running HDTach to spin up my HDD for a while.  Using a basic Radioshack multimeter I tested the rails and voltages of the PSU for consistency and variance.  At idle, I was getting a nice little 11.9v on the rail.  Even at full load I was still only getting a 11.87, which is very little fluctuation.  Stability is important when dealing with electricity.  The last thing you want is to fry your entire PC from an overload provided by your PSU.

	Ultra X3 800W vs. Corsair TX-750W 12v 12v variance 5v 5v variance 3.3v 3.3v variance Ultra X3 800W Idle 11.9 1% 4.92 2% 3.21 3% Corsair TX-750W Idle 12.3 1% 5.18 1% 3.29 1% Ultra X3 800W Load 11.87 2% 4.86 3% 3.15 5% Corsair TX-750W Load 12.32 1% 5.21 1% 3.29 1%

Ultra’s X3 rails are a little lower than Corsair’s rails, but from my experience Ultra usually has rails on the low end of the spectrum.  The variance differs from the Corsair as well, but stay within the acceptable 5% variance, but the Corsair remains rock-solid even under heavy load.

	Ultra X3 800W Power Supply Efficiency Testing amps volts amps volts amps volts 5v 6A 4.92 12A 4.89 16A 4.86 3.3v 5A 3.21 12A 3.18 16A 3.15 12v 8A 11.9 20A 11.89 40A 11.87 Total Wattage 141W (out) 165W (in) 334W (out) 412W (in) 602W (out) 758W (in) efficiency 85% 81% 79.5%

Our findings are actually a little different than Ultra’s, but the curve is similar.  We received an 85% efficiency at low load levels.  At midrange load levels, we received an 81% effiency rating, which is really what an enthusiast gaming PC will do when everything is maxed out.  It seems unlikely that even an average gamer will pull anywhere near this unit’s advertised 800 watts, unless you’re running triple video cards and peltier coolers.  Even at this extreme load, the unit barely hangs on to an 80% efficiency level.

Once again, at Idle I was getting a constistent 4.92 volts from the unit, going up only 1/10th of a degree during full load setting the maxed output at 5.0 volts.  Once again, little variance.  And then I tested the Idle state of our 3 Volt lines, coming out with a solid 3.2 volts.  After getting the PC up to full speed I was able to get a mirror image 3.2 volts out of the rail.  The full stress test barely moved the higher voltages at all, while the 3V line stayed normal.  Consistency does not seem to be much of a problem for this PSU to maintain.