After months of delays, Advanced Micro Devices' latest processor, a quad-core server chip called Barcelona, is at last expected to hit the market Monday.

The stakes surrounding the release of Barcelona, officially called Quad-Core Opteron, are high. AMD lost ground in the server-chip market to rival Intel in recent quarters and is counting on the new processor to reverse its fortunes.

That won't be easy. While AMD struggled to get the Quad-Core Opteron out of its factories, Intel shipped newer, faster processors expected to compete more closely with the new chip, particularly in the market for high-end servers with four or more processors.

Nevertheless, AMD is counting on technical differences between its quad-core chips and those from Intel to offer better performance while consuming less power.

Nine versions of the Quad-Core Opteron will be available from Monday, all manufactured using a 65nm process. These are the first quad-core chips from AMD and the first server chips from the company made using this technology. Previous server chips were made using a 90nm process.

"We used this opportunity as we move from 90 nanometers (nm) to 65nm to redesign the processor, to be able to optimize and get more efficiency out of it," said John Fruehe, AMD's worldwide business development manager for servers and workstations.

At the high end of the Quad-Core Opteron lineup are chips designed for servers with four or more processors.

The 2GHz 8350 has a thermal design power (TDP) of 95 watts and is priced at $1,019 in 1,000-unit quantities, a standard measure of processor pricing. TDP does not indicate the amount of power that a processor consumes, rather it describes the maximum amount of heat that server makers must be able to dissipate from the chip in extreme circumstances.

The second Quad-Core Opteron designed for multi-chip servers is the 8347, which runs at 1.9GHz and has a 95-watt TDP. The chip is priced at $786.

The range of multi-chip servers also includes two models with a lower TDP, the 8347HE and 8346HE. With a TDP of 68 watts, these chips run at clock speeds of 1.9GHz and 1.8GHz, respectively. They are priced at $873 and $698.

All of the Quad-Core Opteron chips have 512KB of level two cache per processor core, and 2MB of level three cache shared by the four cores.

Five versions of the Quad-Core Opteron will be available for servers with one or two processors.

The Quad-Core Opteron 2350 and 2347 run at speeds of 2GHz and 1.9GHz and have a TDP of 95 watts. The chips are priced at $389 and $316, respectively. The 1.9GHz 2347HE, 1.8GHz 2346HE, and 1.7GHz 2344HE have a lower TDP, at 68 watts. The chips will cost $377, $255, and $209.

AMD said the new chips are faster than previous Opterons, with a 2GHz Quad-Core Opteron running 79 percent faster than a 3GHz dual-core Opteron. Five single-core Opteron processors are required to match the performance of a single Quad-Core Opteron, the company said.

The Quad-Core Opteron has four processor cores on a silicon chip that also includes a memory controller hub and high-speed HyperTransport links. By comparison, Intel's quad-core processors have two dual-core silicon chips inside a multi-chip package that does not include the memory controller.

AMD has added new features to the Quad-Core Opteron designed to boost the chip's performance and lower power consumption relative to earlier Opteron chips. For example, each of the Quad-Core Opteron's processors and the memory controller have independent power supplies, which allows them to run at different clock speeds and reduce power consumption when they don't need to run at full speed.