Calxeda, the Austin, Texas, producer of ARM-based servers, took a step closer to becoming a data center alternative to Intel Tuesday when it received $55 million in funding from a set of venture capital backers.

One of them, Vulcan Capital, was co-founded by Paul Allen, one of the original founders of the x86-software empire established by Microsoft. Vulcan is betting that the ARM architecture, used to power cellphones, tablets, and other low-energy devices, will be a suitable chip for future energy-conserving data centers. Austin Ventures also participated in the latest round of funding, which brings the total investment in four-year-old Calxeda to over $100 million. It was launched four years ago with $48 million in backing.

HP last November said it would build Redstone servers as a low-energy consuming server for a limited market of large Web companies--builders of large data centers for conducting search, online games, and social networking. Facebook is known to be evaluating an ARM server design. HP says an ARM chip uses 89% less power than conventional, x86 servers.

[ Want to learn more about how HP produces ARM servers for specialized cloud data centers customers? See HP Plans Low-Power Servers Using Calxeda ARM Chips. ]

"This significant infusion of capital will accelerate the exciting trajectory we've been on for the past four years," Barry Evans, CEO of Calxeda, said in announcing the second-round funding. "Businesses require a more efficient solution for the Web, cloud, and big data," added Evans, the firm's co-founder.

Intel spokesmen dispute some claims for ARM chips, saying they don't do the same amount of work as its x86 architecture. It's also adding more power modulation to its Xeon family, enabling it to use less power during periods of lighter work.

But the world's rapid expansion of data center building and use, through such devices as smartphones and tablets, has some observers alarmed that a major new environmental impact is being created at a time of concern over global warming. The New York Times published a front-page story Sept. 23, "Power, Pollution and the Internet," that cited growing electricity consumption caused by the rapid build-out of data centers and smart-device use.

Not everyone agreed, as witnessed by comments about my column in InformationWeek responding to the story.

ARM chips are designed to sip power off the small batteries used by portable tablets and smartphones. Calxeda has taken the architecture and designed silicon and software to power ARM servers. The chip architecture is hampered by its limited compatibility with the large existing portfolios of x86 software. But the five-watt chips run cooler than Xeons and don't require fans or special data center cooling systems, which are large consumers of power in traditional chip architectures.

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