In an interview with extremetech, Bell said he sees no data that supports the claims that ARM is more efficient.
He said that for a long time, Intel tried to battle this myth with PowerPoint presentations. The only real way to do it is to build an actual device and say "Look, go measure it yourself".
The Medfield-powered Xolo X900, which was benchmarked earlier in the year, falls slightly behind in some tests, but pulls ahead in others.
Intel is not the lowest in power consumption, but was the lowest in some things. Its chips are slower at doing 1080p video but higher than other phones doing 720p. But those same phones can't do 1080p.
Intel chips were better at standby, while performance-wise, x86 chips either exceed by a large amount, or are roughly the same. In some cases Intel chips use less power during the benchmarks.
Bell also dismissed the idea of an x86 power "tax." This is the theory that x86 is less efficient than ARM because it has to support legacy code.
But Bell said that there is nothing in the instruction set that is more or less energy efficient than any other instruction set.
He added that it was all about the implementation and the process technology; whether you target power, or speed, or both.