CPUs in the lower price segment often attract potential customers not only because they can help save a few bucks but also since they boast minimal heat dissipation and power consumption. New Celeron processors based on 45 nm cores can be considered pretty energy-efficient solutions, at least among LGA775 processors. Of course, they can’t compete against Intel Aton in power consumption, but they boast higher performance that exceeds that of Atom processors by several times.
The numbers below show the total power consumption of the tested platforms (without the monitor). During our tests we used 64-bit LinX 0.5.8 utility to load the systems to the utmost extent. Moreover, to ensure that we estimate the power consumption in idle mode correctly we activated all power-saving technologies, such as C1E, Cool'n'Quiet 3.0 and Enhanced Intel SpeedStep.
In idle mode when all power-saving technologies are activated, systems with different processors demonstrate pretty similar power consumption levels. Only the results of the Celeron E1000 based system stand out, because this CPU is built on a core manufactured with old technological process.
However, under heavier load the energy-efficiency of the new Celeron processors shows its real best. The system with a Celeron E3300 consumes 9 W less than a Pentium E5200 platform and 15 W less than a system with Celeron E1600. In other words, new Celeron CPUs are currently the most economical LGA775 desktop processors out there.
By the way, we carried out a separate experiment to measure the power consumption of the CPU alone, independent of the rest of the system hardware components. In this case we measured the consumption along the 12 V power line connected directly to the processor voltage regulator on the mainboard. In other words, this measurement method took into account the efficiency of the voltage regulator circuitry.
It turned out that the minimal power consumption of the new Celeron processors is about 20 W, which is a very impressive result. It means that Celeron E3000 processors can be used in energy-efficient systems with total power consumption no higher than 50 W under peak load when paired with mainboards based on chipsets with integrated graphics core.