As we have already found out, the AMD Brazos platform is all right in terms of performance, at least if used in netbooks and nettops. However, these devices also require that the platform had low power consumption and heat dissipation. The Bobcat microarchitecture was designed to be highly energy-efficiency and the TDP of Zacate APUs only 18 watts. But what do we have in practice, especially in comparison with the existing and quite successful ION platform?
The graphs below show the full power draw of the computer (without the monitor) measured after the power supply. It is the total of the power consumption of all the system components. The PSU's efficiency is not taken into account. The CPUs are loaded by running the 64-bit LinX 0.6.4 utility. Graphics cores were loaded using FurMark 1.8.2 utility. Moreover, we enabled all power-saving technologies to ensure that computer power draw in idle mode was measured correctly
When doing no work at all, the Brazos has fantastically low power consumption. In fact, it is the most economical platform in idle mode that we have ever seen and tested. Clearly, AMD made a right decision by implementing deep power-saving states in its new energy-efficient processor microarchitecture. The turning off of unused circuits in the semiconductor die comes in handy, too.
By the way, Intel’s Atom processors are not that progressive in this respect. Trying to make them cheaper, Intel cut off a lot of technologies that help minimize power consumption in idle mode. On the other hand, the rather high power draw of both versions of the ION platform is due to the chipset and graphics core rather than to the CPU.
The AMD Brazos remains the most economical nettop-oriented platform under high computing load, too. The difference from the second-generation ION amounts to 5 watts although the Zacate’s TDP is 5 watts higher than that of the Atom D525.
The graphics load emphasizes the high energy efficiency of the AMD Brazos platform even more. Although the Radeon HD 6310 graphics core integrated into the AMD Zacate processor delivers high performance, it is absolutely blameless in terms of power consumption.
We can see everything even more clearly when the systems are under full load, the computing and graphics cores all together. AMD has developed a very economical platform for nettops and netbooks which can compete with the best available alternatives. The results of our tests suggest that Brazos-based netbooks are going to have a very long battery life.
HD video playback is yet another kind of complex load. When used as a video player, our systems do not change their standings in terms of power consumption, though. The AMD Brazos needs only half the power that the second-generation ION consumes. The first-generation ION is more voracious than the Brazos, too.
Considering these results, we guess we should be disappointed that our Brazos-based MSI E350IS-E45 mainboard is equipped with active cooling. The Zacate processor can obviously do with only a passive heatsink unless it is a bare chunk of aluminum with no fins at all. Hopefully, mainboard makers will release AMD-based products for nettops without such small and load fans as the one installed on our MSI mainboard.