IBM's Unix power play - Power5 launches

IBM is expected to announce a new generation of Unix servers today, systems it believes powerful enough to let Big Blue topple rivals HP and Sun Microsystems.

IBM will announce low-end and midrange models using the new Power5 processor: the dual-processor eServer p5 520, the four-processor p5 550 and the 16-processor p5 570. The systems, which boost performance and can run many operating systems simultaneously, will ship by 31 August.

The products are strong, analysts say, and arrive at a time when Sun and Hewlett-Packard, the number one and two Unix server sellers, are vulnerable. "Sun and HP have begun refreshes to technologies that are competitive but they're not there yet," Forrester analyst Brad Day said.

Illuminata analyst Jonathan Eunice had a similar assessment. "IBM is at a very strong point in its product cycle right now. Its competitors are at a bit of an ebb because of their transitional issues," Eunice said, referring to Sun's embrace of Fujitsu's high-end Sparc64 processor and HP's switch from its PA-RISC chips to Intel's Itanium.

For the first time, the p5 systems use identical hardware as their i5 server brethren, which debuted in May. That convergence means a larger customer base supports IBM engineering resources and that three operating systems - IBM's AIX version of Unix, its i5/OS for mid-range machines and Linux from either Red Hat or Novell - now can run at the same time on the same systems.

The higher-end Unix models are due by the end of the year, including a 64-processor model, said Ravi Arimilli, chief technology officer of eServer microprocessors and systems development and an IBM fellow. And if customers express an interest, a 128-processor machine could be built when systems using the smaller, faster Power5+ arrive in 2005, he added.

The Unix server market is a sweet spot for server makers, nicely positioned between mainframe power and high price on the one hand and Microsoft Windows' broad software support but relative immaturity on the other. IBM missed out on the Unix boom of the 1990s, when lavish spending poured money into Sun's coffers.

With the Power4 generation and Sun's troubles, IBM has been gaining Unix share. In 2003, IBM's revenue grew 13 per cent to $4.1bn, while Sun's shrank 16 per cent to $5.4bn and HP's shrank 4 per cent to $5.3bn, according to research firm Gartner.

IBM admits it was caught flat-footed by Sun's surge. "When I was appointed chief architect for Power, the game was simple. We had to get back into the game. Power4 was do-or-die mission. We had to get running fast because our market share was so small," Arimilli said.

IBM has a simple future planned for the Power line: Power5 this year, a faster remake called Power5+ in 2005, Power6 in 2006, Power6+ in 2007, Power7 in 2008 and Power7+ in 2009, said Arimilli, who has just been named chief architect of the Power7 models.

For more on Power5 and what HP and Sun are offering, click here.

Stephen Shankland writes for CNET News.com.