AMD has released a new version of its Opteron processor, the popular server chip that has made AMD a serious competitor of rival, Intel.

Vendors including HP, IBM and Sun Microsystems have announced plans to sell servers using the new "Rev F" chip -- formally the Next-Generation AMD Opteron Processor.

Vendors applaud the chip's support of virtualisation and DDR2 memory, and its ability to maintain constant electrical and thermal boundaries as it rises from dual-core design today to quad-core in 2007.

"Opteron's success stems from its simplicity. When we changed from single to dual core, we maintained the same socket, thermals and motherboard. That keeps it predictable for IT managers as they plan their data centres," director of North America commercial business for AMD, Vladimir Rozanovich, said.

AMD hopes the chip will preserve its recent gains in market share. The company has watched sales rocket up with Opteron, which is popular with customers who like its power-efficient processing in an age of soaring costs for data center power and cooling.

That popularity has driven server sellers like Dell and IBM to launch AMD-based machines in recent months. By the end of 2006, Opteron chips will be used in 50 tier-one server platforms; double the number in 2005, Rozanovich said.

Indeed, AMD posted 25.9 per cent share of the market for x86-based servers in the second quarter of 2006, a 133 per cent increase from the same quarter last year, according to Mercury Research.

To illustrate the importance of Opteron in AMD's portfolio, its market share for all chips -- including desktop, mobile and server -- was only 21.6 per cent that quarter.

The rest of the market belongs to Intel, which struck a blow against Opteron in June with the launch of its Woodcrest Xeon 5100 server chip, a member of the company's Core 2 Duo generation of power-efficient chips built with 65-nanometer architecture.

Now AMD hopes to regain its momentum with the Rev F chip.

AMD will sell the new Opteron in three power levels. The mainstream line runs at 95 watts, appropriate for tier-one vendors including Dell, HP, Sun and IBM as well as smaller sellers like Rackable Systems, Egenera, Fujitsu and Appro International, Rozanovich said.

A high-performance SE version will run at 120W for a series of Sun servers, and a low power HE version will run at 68W for blade servers used in the financial services and oil and gas exploration markets.

AMD further divides the new chip line into three server sizes. The Opteron 1000 series are appropriate for single-chip servers and workstations, while the 2000 series will fit two-processor machines and the 8000 series will fit four- and eight-chip machines.

The lion's share of sales would come in the two-chip server market, which accounted for 80 per cent of all x86 servers, Rozanovich said. Most of the remainder would come in the fast-growing four-chip server segment.

Priced in one thousand-unit quantities, the chips cost $US2149 for the Opteron 8218, $US873 for the Opteron 2218 and $US749 for the Opteron 1218. All three chips run at 2.6GHz, but other variations range from 1.8GHz to 2.8GHz.

HP plans to use the Rev F chip in six new products: the ProLiant DL385 G2 and DL585 G2 rack-optimised servers, and the BL25p G2, BL45p G2, BL465c and BL685c server blades. The company has not announced prices, but plans to ship all six products during the fourth quarter of 2006.

HP credits the new Opteron chip with helping create a 15 per cent performance boost comparing the DL585 G1 to DL585G2. That improvement also comes from HP's decision to shrink its disk drives from 3.5 inches to 2.5 inches.

Sun will use Rev F Opteron chips in its Sun Fire X2100 M2 and X2200 M2 servers, relying on the new technology to compete against products like HP's D1320 G4, Dell's PowerEdge 850 and IBM's xServer 306m.

Compared to competing servers with Intel's Woodcrest Xeon 5160 chip, Sun said its Opteron-based X2200 had 36 per cent better performance with 15 per cent less power consumption.

Sun expects to ship the products later in August, selling the X2100 server for $US945 and the X2200 for $US1595.