3 - Going Greener | Overclocking features

New Power Saving States

To give a little context to this review, I want to let you know that we were a little short on time to do all the testing. But what I wanted to make you aware of is that the board is pretty power consumption aware, we'll show you some wattage numbers later on though. The 790GX incorporates four power-saving improvements that you supposedly don't have on the 780G boards

• A deep sleep on the side-port memory, yielding up to 1.7 W of savings.
• Driver and BIOS enhancements made to AMDs PowerPlay technology -- save up to 3.1 W as well.
• Onboard voltage scaling --  another 900 mW
• Support for the C1e power state approaches 6 W of savings.

AMD has made some power savings enhancements with the 790GX, offering a deep sleep mode for the sideband memory, voltage scaling, enhanced PowerPlay features, and a new lower power CPU state. As you can see power management at work. In idle the 2400 MHz CPU clocks down to 1250 MHz, one of the many energy aware functions.

When we actually measure, as you can see, the power consumption is pretty good, actually.

In an idle state the 790GX mainboard without a graphics card installed utilized 97 Watts, with a graphics card installed you'll jump towards 155 Watt.

Once we start utilizing the four CPU cores the wattage jumps up quickly. 217 Watts with 4 cores stressed and no VGA installed. And 290 Watts with a graphics card installed. In this last situation I had a Radeon HD 4870 X2 installed, which apparently pushed up power consumption overall a little opposed to the 3870 in all other circumstances.

I must say, though the power management features work great, I still find the Phenom X4 processors to be a tad on the power hungry side. Once you start overclocking a Phenom then things will get way out of control though, these CPUs suck up a lot of power when you run them beyond specifications.

AMD Overdrive -- overclocking

Key to the new 790GX feature set is AMD's Overdrive interface that allows effortless overclocking of the Phenom Black Edition processors. The significant performance increase the platform can deliver to gamers using Black Edition processors is thanks to what AMD calls Advanced Clock Calibration technology. The new B3 Phenom processors can complement the 790GX chipset's overclocking capabilities very well, and AMD reports that Phenom Black Edition processors running at 2.5GHz stock can be pushed to 3.2GHz and over thanks to its new Advanced Clock Calibration.

ACC, short for Advanced Clock Calibration, was planned to enhance the overclocking potential of Phenom processors. AMD hasn't revealed exactly how the technology works, even at a recent AMD technology summit the details were not handed out. But one fact is that the Southbridge has a dedicated link to the CPU. We think it boils down to ACC's ability to keep clock frequencies in sync and stabilize inter-chip communications between the CPU, Northbridge, Southbridge and memory. Mind you that this trick only works for Phenom processors, particularly for the Black Edition processors actually.

We obviously gave it a try and were able to reach much higher clocks frequencies perfectly stable on the fly.

AMD's Overdrive software overclocking the Phenom X2 towards 3100 MHz easily

Reportedly some people have been able to reach much high results. I also gave overclocking the HT frequency combined with a higher multiplier and boosted the CPU voltage a little. Again we were pretty easily able to hit 3.1 GHz on a stock Asaka air cooler.

Anyway, let's have a look at what ECS has to offer feature and bundle wise.