Roundup: Seven Power Supply Units from Antec

Tag : usb power supply
This PSU features a system of monitoring of the currents andvoltages, and a USB interface into the bargain. I connected thelatter to a nearby PC and launched the Power Tuner tool on it.Thanks to this program I could keep track of the power consumptionof my testbed continuously, right from the moment I turned it on.The Odin GT is sufficiently accurate, especially at high loads. Ofcourse, I could arrange a set of shunts and measure the currents ina more honest way but it would improve the precision but slightly(within 10-20W) while making the whole test much more difficult toperform.
I’d like to give you my opinion about two myths, by the way.
Myth One: increasing the number of fans or USB devices raises thePSU load greatly. As a matter of fact, you can just look at theconsumption of both to see this is untrue. USB is limited to 2.5W(a current of 500mA at a voltage of 5V) while a regular fanconsumes no more than 3-4W. You’ll need some two dozen fansto beat the consumption of a single graphics card!
Well, if your system is on the verge of becoming unstable (due tolack of power or low quality of the PSU), even one fan may beenough to get it beyond that verge. But in this case you shouldthink about the adequacy of the PSU at large rather than about thepower consumption of your fans. A stable system, which has areasonable reserve of power, just cannot be affected by USB devicesand fans.
Myth Two: a PC with a large number of hard disks needs a lot ofpower to start up. In fact, a modern HDD has modest powerrequirements, about 12-15W under load. The spinning-up of itsplatters at system start-up requires far less power than a moderngraphics card is consuming in 3D mode. In fact, it is in gameswhich simultaneously load both the graphics card and the CPU (theseare the two main consumers in modern PCs) that your system may feela lack of power. If your system with a 400W PSU refuses to start upwhen you add a fifth or sixth hard disk, you should blame thequality of the PSU rather than its wattage.
So, I performed the test in four modes: 1) Idle, 2) full load onboth CPU cores by means of Prime95, 3) full load on all the fourHDDs by means of IOMeter, and 4) 3DMark06, the most interestingmode from a practical point of view. In every mode I noted thehighest peak of power consumption.
The table below shows the power consumption of my configurationfrom the PSU (not from the wall outlet, so you don’t have totake the PSU efficiency into account).

As you can see, a system with an advanced CPU, a top-end graphicscard, and four fast HDDs has a peak power consumption of only 210W!Well, I was not surprised at the results at all as we hadpreviously measured the consumption of individual CPUs , graphics cards and hard disk drives in our reviews, but the overall consumption numbers make it alleven clearer.
Most customers have overestimated notions about the powerrequirements of their PCs. I won’t discuss that further. Iwill just mark the points corresponding to these values in thecross-load diagrams of the tested PSUs.