AOpen Powermaster: The Motherboard of All CPU Power-Saving Solutions?

Features Table

Common Sense Rules

Even if we must add a disclaimer to our power dissipation measurements because of insufficient time to test as thoroughly as we might have liked, our findings are both quantifiable and significant. A PC outfitted with an i915a-PLF motherboard running in Silent Mode barely gets warm. That is because the power consumption of the Northbridge chipset along with the CPUs is about 15 watts less than a conventional, full-power system with identical components.

That said, we also have to observe that clock rate changes at run-time last longer and take slightly longer to happen compared to AMD's Cool & Quiet or Intel's SpeedStep technologies. If we'd had time to run our full suite of benchmarks against the AOpen motherboard, Silent Mode may have performed worse than our abbreviated testing could show. In Normal mode, however, we observed by random sampling that the AOpen board stayed on par with similar motherboards from lots of other vendors.

An interesting combination would be to use the Powermaster motherboard with a CPU that supports Enhanced Speedstep functionality. In the case of Intel's Pentium 4 600-Series the smallest work multiplier under minimal load is 14 (2.8 GHz clock speed with a 200 MHz FSB). The Powermaster board would use this to set the CPU's clock speed at about 1.96 GHz, with bus speed of about 140 MHz (thus maintaining the same work multiplier). Because SpeedStep also supports dynamic power adjustment, this leads to even greater power savings. But we'll have to leave this potentially powerful (and interesting) combination for a future test.

In its next generation of products, AOpen should work on dynamic input voltage management for other system components, if only minimally. If the Northbridge and DDR400-connector chipsets were also underclocked, this would lower power consumption still further. But what affects the CPU is critical, so it's also important to make sure that SpeedStep and Powermaster don't step on each other's toes (or worse still, attempt to implement conflicting settings).

What's much more important, however, is the future promise for motherboards with advanced power management (and underclocking) that the AOpen i915a-PLF offers. Powermaster does not just reducenoise and power consumption, but represents a step in the right direction towards a more environmentally-friendly system.