Standard Performance Evaluation (SPEC), which creates performance benchmarks for servers, has released a test suite that is designed to let users compare servers on the basis of energy efficiency.

Five server vendors helped develop the new benchmark, as did Intel and AMD.

A similar initiative is under way at the US Environmental Protection Agency, which is creating a version of its Energy Star rating for servers. Klaus-Dieter Lange, a senior performance engineer at Hewlett-Packard who heads the SPEC subcommittee that developed the benchmark, said he thought the EPA would "adapt what we came up with."

SPEC's benchmark covers only one kind of server workload now. Even so, "having real, measured data is a vast step forward," said Jonathan Koomey, a staff scientist at Lawrence Berkeley National Laboratory and an adviser to the EPA.

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