"You're most likely going to have a quad-core processor with four different speeds because you've got four different utilization levels at any time," Fruehe said.

The chip maker also added a 128-bit floating point unit to the Quad-Core Opteron to boost performance for certain types of applications.

At the same time AMD will announce the availability of the Quad-Core Opteron, the company plans to say more than 50 systems based on the chips are now available from vendors like Sun Microsystems, Hewlett-Packard, IBM, and Dell, among others.

If servers based on the Quad-Core Opteron chips turn out to be faster and more energy efficient than systems based on Intel's offerings, that edge may not last long. In November, Intel plans to refresh the bulk of its server chip lineup with a new family called Penryn. The Penryn server chips will be made using a 45-nm process and will have more memory cache than Intel's existing server chips, giving them a boost in performance.

"We have a significant lead today and we believe we will have that lead with Clovertown, and once we have Harpertown with 45-nm we will extend that lead further," said Adesh Gupta, regional platform architecture manager at Intel Asia-Pacific's Server Platforms Group, referring to code names for Intel's current and upcoming quad-core processors designed for two-way servers.

Later this year, AMD expects to release Quad-Core Opteron chips that run faster than the versions set to be announced Monday. One of those processors is a 2.3GHz Quad-Core Opteron SE designed for high-performance computers, set for release during the fourth quarter.

AMD plans to offer faster versions of the standard Quad-Core Opteron chips during the fourth quarter, with faster versions of the low-power HE chips due during the fourth quarter of 2007 or the first quarter of 2008.