The main concern with mobile computers is battery life. What is the use of a mobile platform with a battery that can last only one hour?

Like processors from both Intel and AMD, VIA C7-M also changes its voltage and frequency depending on the computer usage, saving battery life. But what is unique to C7-M is the use of two clock generators (a.k.a. PLL, Phase Lock Loop). On other CPUs there is just one clock generator and when the CPU needs to lower the clock, it has to send a command to the clock generator, which takes time. On VIA C7-M is just a matter of switching the clock generator, which is faster. According to VIA, on C7-M this process takes only one clock cycle, while on Pentium M the same feature requires 15,000 clock cycles.

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Figure 10: VIA C7-M Power saving features.

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Figure 11: Comparison between VIA TwinTurbo and Intel Enhanced SpeedStep technologies.

VIA claims that the battery of a notebook with C7-M lasts over 5 hours of continuous operation.