Advanced Micro Devices this week unveiled an energy-efficient, dual-core Athlon desktop processor.

The 45-watt, X2 4850E processor is designed to reduce power consumption, offering greater performance-per-watt. AMD noted that the new chip's predecessor, the Athlon X2 4800 dual-core, was only available in the 65-watt power envelope.

The new 4850E chip has the same specs as the 4800 -- 2.5GHz, 1MB of total dedicated L2 cache, a 2000MHz HyperTransport bus - but consumes less power, AMD said.

An AMD spokesman also said the new 4850E processor has the same price tag as its predecessor -- US$89 in 1,000-unit tray quantities.

"This AMD Athlon X2 45-watt processor is the latest effort by AMD to enable energy-efficient platform solutions with technologies such as AMD Cool'n'Quiet," said a spokesman in a statement. The so-called Cool'n Quiet technology is designed to enable PCs to take up less space in cramped offices and cubicles, while also helping them operate quietly, he said.

Releasing the X2 4850E chip had been on AMD's roadmap is shipping ahead of its original schedule. Other variations of the 45-watt Athlon dual-core processors are slated to ship later this year, the company said.

AMD in January had announced that it speeding up the release of what it's calling an energy-efficient quad-core chip. The 9100E quad-core, which is said to use a third less power than regular Phenom chips, had been slated on in-house road maps to ship in either the second or third 2008 quarter, but is now on the docket to be released this quarter.

"Our focus is on the energy-efficient products and triple-core products," AMD spokesman John Taylor said.