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 with this setup, in fact I remember this setup peaking to 800W at one point with a PSU. 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 a professional watt-meter (thus we measure in-between PC and wall socket).
The reality is very interesting, where we passed 750W two years ago with all that equipment and overclock we are barely able to pass ~700 Watts load.
Now mind you, this is a 625W PSU, with an allowed peak to 690W. It however was not an issue.
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 roughly 1 Watts only. We had so much gear plugged into this system, the power consumption remained fairly low, making me believe that 84%~88 power efficiency is very plausible.
Great stuff really and on par with a lot of other high quality high efficiency PSUs we've tested.
Out of pure curiosity I also connected the PSU towards a new P67 / Core i7 2600K platform. Check this out, a new Gigabyte P67A-UD4 on a BFG 1200W PSU in idle measures up to 84W and under CPU load 159W.
Now we replace the PSU with the Enermax Modu 82+II and in idle we now measure 78W and under CPU load 146W. And that's the difference in efficiency. Surely a few watts won't bother you, but with massive power consumption you can shave off 50 to 100W compared to old PSUs at high load.
ErP - Now then, new in the revised Modu82+ II and Pro82+ II series is that they support the new EU regulation ErP Lot 6 for PC systems. This norm regulates the standby consumption of systems, which affects PSU and mainboard.
Basically in standby the PC system should not consume more than 1W during off-state or standby. From the 7th of January 2013 on, the limit will be 0,5W. We tested that with the latest ErP compatible P67 motherboard from Gigabyte and indeed, we notice a 1.1V standby power consumption.
When we place the PC into sleep mode we measure 0.9 to 1.6v power consumption, it would fluctuate a little bit but it's testimony that the feature really works well.
