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Two months after introducing the Power5 processors in a line of new systems running its OS/400 operating system, IBM on Tuesday is unveiling Unix servers running the new chip.

IBM, of Armonk, N.Y., will roll out three new servers that will hold from two to 16 processors and run the newest version of its Unix operating system, AIX 5L v5.3, as well as Linux.

The introduction of the P5 is the next step in the convergence of IBM’s Power-based i- and pSeries systems as the company continues to simplify its hardware offerings, though officials say there will still be a distinction between the two lines.

In May, IBM introduced the first of its eServer i5 systems, a departure from the iSeries name. The company also introduced the latest version of its OS/400 operating system, named i5/OS.

The systems introduced Tuesday will be the eServer p5 systems, including the two-way p5-520, four-way p5-550 and the midrange p5-570, which will scale up to 16 processors. The first two will use the Power5 chips, up to 1.65GHz, with the p5-570 running 1.9GHz chips.

The midrange server also offers further evidence of the convergence. Like the other two, it will run AIX 5L or Linux, but it also will run i5/OS.

In addition, an express version of the p5-570 will run 1.5GHz chips and include up to 256GB of memory.

However, there will continue to be distinction between the two lines, said Karl Freund, vice president of pSeries products. While the i5 systems, aimed at small and midsize customers, will offer integrated packages that feature IBM middleware—including Tivoli, WebSphere and DB2—Freund said, the pSeries systems will continue to be more customizable.

Still, the two lines will share the partitioning and virtualization capabilities available with the Power5. Included in the chip is IBM’s Virtualization Engine, which includes the Micro-Partitioning feature. Users will be able to run up to 10 virtual servers on a single processor, with each server able to run a different operating system, and can run workloads across those partitions, Freund said.

That capability—which IBM is bringing into its enterprise systems from its mainframe servers—will enable businesses to increase the utilization of their systems while reducing the cost of operating them. In addition, the dual-core Power5 offers multithreading capabilities on each core, increasing the performance of the chips, Freund said. The new version of AIX 5L takes advantage of these capabilities by enabling such features as the virtual I/O and LAN, as well as the multithreading, he said.

“The years of innovation that we’ve done with the mainframe, we are applying now [to other server lines],” he said.

That innovation includes integrating some memory and task management features directly onto the silicon.

The virtualization and partitioning capabilities are the key part of the new chip, beyond the simple bump in processing power, said Gordon Haff, an analyst with Illuminata Inc., in Nashua, N.H.

“The reality is that all that plays a larger role [among users] today, rather than just improving processor performance,” Haff said.

IBM for months has been pushing its Linux-on-Power initiative, driving to make Power the architecture of choice for Linux users. However, Unix continues to be a growth area for the company, Freund said. Though the Unix market has stabilized at about $20 billion per year, IBM aims to grow by stealing share from competitors—primarily Hewlett-Packard Co. and Sun Microsystems Inc. Numbers from research firms IDC and Gartner Inc. indicate that IBM grew Unix revenue in 2003, while HP and Sun saw revenues decline.

Officials with both companies criticized IBM’s Power5 push, saying that it can’t be an open architecture when it can’t run Windows and that it forces customers to migrate to new hardware and OS support.

Freund said that IBM offers the xSeries for Windows as well as Linux, and that IBM has a migration offering that gives users a clear path to the Power5 systems. In addition, he said, the new Power5 systems can interoperate with the current Power4 systems, and the Power4 systems can be transitioned to Power5 one virtual partition at a time, with no downtime.

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