Energy consumptionWe measured the energy consumption of the different motherboards. Each board was tested with a Core i7 2700K processor, which was also used for the graphics part. Our configuration here differs from the one used for the overclocking readings. We used four memory bars on the system, clocked at 1600 MHz and supplied at 1.5V. A single hard drive was plugged into the machine and we used the IGP for the graphics part. The figures therefore aren’t comparable to those obtained on the previous page!
We measured the total energy consumption of the platform at idle, in processor load (Prime 95) and in processor + graphics card load (Prime 95 + Furmark).
Note that some motherboards offer energy economy modes which sometimes lower certain voltages. We have added them to our comparative below. We have only added the modes which don’t change performance however.
At idle, the energy consumption of our mobos is relatively similar, with a small advantage for MSI. In load and without the energy economy mode, Asus is on a par with MSI. ASrock and Gigabyte consume significantly more power in load. Activating the energy economy mode on the ASRock makes a definite difference however. Remember, this mode reduces the number of phases used in load!
To finish up, we tried to measure the temperatures of the mobo power supply circuits. We placed the boards in a Lian Li PC-P50 R casing and measured the temperature at the back of the VRM circuits with an infrared thermometer by cutting through the plate that supports the motherboard. Two fans were plugged into the casing, one low down at the front in front of the hard drive running at 600 RPM and the second running at 1100 RPM as an extractor at the back.
Not all the motherboards are designed in the same way, with, as we have seen, ASRock reducing the size of its mobo significantly and placing its VRM processors above the socket. This is what our mobos look like from the back:
[ ASRock ] [ Asus ] [ Gigabyte ] [ MSI ]
As you can see, the ASRock board stands out from the others with a differently placed socket. We therefore decided to measure the heat at three points:
- The hot point on the right part of the VRM
- The hot point on the top part of the VRM
- The hot point between the socket and the right VRM
We tried to take a reading at the right part of the VRM on the ASRock board but the reading here was less precise. We measured these temperatures after ten minutes of load in Prime 95 in two configurations, by default (with XMP profile) and with our processor overclocked to 4.5 GHz.
[ 3.5 GHz ] [ 4.5 GHz ]
Firstly, in comparison to our previous review
, even at the initial clock, the temperature is significantly higher. All the models are at least ten degrees hotter. This isn’t a surprise because in spreading the load across more VRMs and therefore also over a bigger area, localised heating is reduced.
The ASRock board is penalised most by the positioning of its VRMs, which both benefit less from extraction and have our processor radiator underneath them. This naturally heats things up. At 4.5 GHz, the ASRock mobo shows its limitations and this partly explains the overclocking difficulties it experiences. Of course, the quality of the VRMs in themselves may also be a reason for this, though this is difficult to verify.
Note finally that at 4.8 GHz, under the same conditions, the power supply circuits on the medium range boards were a good 20° cooler.