AMD 's long awaited quad-core CPU will finally appear in August with a maximum clockspeed of just 2GHz. That's the official - and frankly rather disappointing - news following an official AMD announcement.

Codenamed Barcelona and also known as the K10 architecture, AMD's first quad-core CPU will initially be sold under the Opteron brand for use in servers and workstation PCs. The chips are drop-in compatible with existing current-generation Opteron motherboards, while regular desktop chips based on the K10 core are expected to arrive in the first quarter of 2008.

AMD does hope to ship faster Barcelona chips later in 2007. According to the announcement, "AMD expects its native quad-core processors to scale to higher frequencies in Q407 in both standard and SE (Special Edition) versions."

Earlier this year, leaked road maps for Barcelona indicated that AMD had hoped to launch the crucial new CPU at around 2.5GHz. For now, AMD is claiming that the disappointing launch frequency is a result of a decision to focus on power efficiency, often referred to as performance-per-watt.

According to senor AMD operative Randy Allen, "AMD has prioritised production of our low power and standard power products because our customers and ecosystem demand it. And we firmly believe that the introduction of our native Quad-Core AMD Opteron processor will deliver on the promise of the highest levels of performance-per-watt the industry has ever seen."

That may well be true. But there's also little doubting AMD would dearly like to ship Barcelona at speeds well in excess of 2GHz.

Full technical specifications for the K10 architecture have yet to be released. But AMD has revealed the chip will boast much improved floating point and SSE performance. An upgraded memory controller and faster HyperTransport links will be among other detail enhancements.

However, K10 is not thought to be a major departure from the existing K8 Athlon and Opteron cores. Hence, it's hard to imagine it being anymore than reasonably competitive with Intel's quad-core processors on a core-for-core and clock-for-clock basis.

But with a maximum speed of 2GHz, the first Barcelona chips will lag Intel's quad-core processors by a massive 1GHz. It's thought AMD plans to launch its first quad-core desktop chips at around 2.6GHz. By the time they are launched early next year, Intel could well be shipping 45nm Core 2 Quad chips at well over 3GHz.