Chip designer ARM says processors using its cores can match Intel's new Atoms "toe to toe" on performance per megahertz and beat them on power efficiency.

Bob Morris, director of mobile computing, pointed out that ARM cores already drive devices such as Apple's iPhone and Nokia's N800 series, which were forms of the Mobile Internet Devices (MIDs) that the Atom is designed for.

"The iPhone uses an ARM 11 core, we think running at 300-400MHZ. The user experience on that is very good. Products… coming out later this year will run our Cortex A8 cores which have a 2x to 3x increase in performance."

ARM also has an A9 architecture supporting multiple cores but that will take some time to filter through into products. Unlike Intel, ARM sells designs to other companies who pack peripheral functions around its cores to create systems-on-a-chip.

Morris pointed out: "This is not a case of Intel versus ARM. It’s Intel versus Samsung, Texas Instruments, Qualcomm and Broadcomm, all of which have been making mobile products for years. They have all the radios integrated into chips, which Intel is still working on."

TI's A8-based OMAP 3430 SoC supports 720p HD playback, XGA resolution, 12 megapixel cameras, DVD quality and Imagination Technology’s PowerVR SGX graphics. The Atom graphics are on separate chip.

But the biggest difference, according to Morris, will be in standby power.

"The leakage is the killer… ARM partners know how to power things down. You can leave you smartphone in your pocket at weekends and pick it up and you still have charge."

This is important in devices that may need to be always on, to check for emails, or to be ready for instant use when taken out of the pocket, Morris said. He was speaking before the Intel Developer Forum opened this week, when Intel released details of the Atoms – including the fact that all but the slowest draw 100mw on standby.

This figure does not include the drain of the peripheral chip, which packs the Atom graphics. Morris reckoned that ARM chips would draw a twentieth of the power on standby.

Morris claimed A8-based processors would also have the power to run Linux-based ultra-mobiles like the Asus Eeee PC.

He said Intel was forced to enter the market because sales of mobile connected devices are expected to soar over the next couple of years.

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