Load testing the PSU
Load testing the PSU
As you can see, we had a bit of a challenge at hand. I mean without professional Chroma load testers it's pretty hard to stress a power supply of this class and actually measure its behavior.
So here's what we did. We use, what is now to be considered 'old gear', a power hungry nForce 790i SLI motherboard. We take two GeForce GTX 295s (thus four GPUs) for some serious power consumption.
Then we add in another GeForce GTX 280 purely for PhysX as well. Next, we take a power hungry QX9770 processor and overclock it to 3600 MHz (the one with the 1600 MHz FSB). Then we overclock our memory as well.
These are the components used:
- nForce 790i motherboard (has high power consumption)
- Core 2 Quad QX 9770 Processor (overclocked to 3.6 GHz)
- 2x GeForce GTX 295 primary (4 GPUs)
- 1x GeForce GTX 280 (PhysX)
- 3 GB Memory DDR3 @ 1600 MHz
- Optical Drive x1
- HDD x1
Now two years ago we'd reach 750 Watts power consumption, in fact I remember this setup reaching over 800W at one point. But with power supplies getting more and more efficient these days... that proves to be a very hard task to accomplish. We gave it our best though. Let's have a look at the test results.
In the screenshot below you can see the five GPUs we have installed and activated in this PC. For our test we used several pieces of software which allows us to go hard on the GTX 295s (Quad SLI) but also use Physx on that additional GeForce GTX 280. For this test run we simply monitor the watt-meter (thus we measure at the wall socket).
The reality is very interesting, where we passed 750W two years ago with all that equipment and overclock we are just unable to pass ~700 Watts load. As stated, a year or two ago with this very system we'd have passed 800 Watts. PSUs themselves are becoming more and more efficient and thus greener as well, in the end saving on overall power draw from the wall socket, and that in return saves you money on the power bill.
Some notes here. Powered down the PSU consumes very little current, we measured ~2 Watts only. We had so much gear plugged into this system, the power consumption remained fairly low, making me believe that 85%~91% power efficiency is very plausible.
Great stuff really and on par with a lot of other high quality high efficiency PSUs we've tested.
