We performed our power consumption measurements using an Extech Power Analyzer 380803. This device is connected before the PSU and measures the power draw of the entire system (without the monitor), including the power loss that occurs in the PSU itself. In the idle mode we start the system up and wait until it stops accessing the hard disk. Then we use LinX to load the CPU. For a more illustrative picture there are graphs that show how the computer’s power consumption grows up depending on the number of active execution threads in LinX (both at the default and overclocked system settings). The mainboards are sorted in alphabetical order on the diagrams.
We often point out that on many mainboards certain power-saving technologies are disabled by default. This time we decided to illustrate our discontent with this issue with numbers. We measured the power consumption of test systems in idle mode with default settings and then with all power-saving technologies manually enabled.
As opposed to ASUS’s flagship products, the Cool’n’Quiet and C1E technologies work on both mainboards by default. It turned out that enabling the exclusive EPU technology and the dynamic regulation of the number of active phases in the CPU voltage regulator did not affect the power consumption of the mainboards. We can’t judge these technologies basing on the test in idle mode, though. So, we carried out a range of tests at different loads with the M5A97 EVO.
It’s Cool’n’Quiet, C1E and C6 features that help lower the mainboard’s power consumption in idle mode. They are turned on by default and ASUS’s exclusive technologies do not affect the mainboard’s idle power draw which is 82 watts. However, they do have a positive effect when the computer is running some applications. With these technologies turned on, the power consumption at eight execution threads is only 222 watts, which is even lower than at four threads with the exclusive power-saving technologies turned off (228 watts).
We want to remind you that we carry out our power consumption tests at the default settings, therefore the consumption of the ASUS mainboards is higher in the next diagram than with enabled CPU Power Phase Control and EPU. Overall, the M5A97 EVO is average in terms of power draw while the M5A99X EVO is more economical than its opponents under load.
On the other hand, the same M5A99X EVO has the highest power consumption when overclocked because we had to increase the CPU voltage higher than usual. The M5A97 EVO looks better than the other ASUS mainboards but only because it couldn’t overclock our CPU to its maximum frequency and had a lower CPU voltage. It should be compared with the MSI 990FXA-GD80 which clocks the CPU at 4.3 GHz too, but is more economical in every mode.
ASUS’s M5A99X EVO and M5A97 EVO mainboards are high-quality products which only differ from their top-end cousins in the variety of additional controllers and expansion slots. Their functionality is board enough and includes all modern interfaces: USB 3.0, SATA 6 Gbit/s, eSATA and IEEE1394 (FireWire). So if you do not plan to use a lot of graphics cards, each of them can be a good choice. The only downside is that the overclocking potential of the junior chipsets is lower than that of the flagship AMD 990FX. And we’re talking about ASUS mainboards which have turned out to be the best choice for overclocking the new Bulldozer series. The results are going to be even more disappointing with other mainboards, we guess.
Anyway, we have no doubt about the bright market future of the M5A99X EVO and M5A97 EVO mainboards. People who look for highest performance prefer Intel whereas AMD users have other priorities. The AMD platform is quite good for building an affordable computer with acceptable performance and these ASUS mainboards cost much less than their flagship counterparts.