IBM will mark the 40th anniversary of the first mainframe computer today by introducing a scaled-down version of its zSeries 990 mainframe servers called the zSeries 890, billed as a mid-market mainframe offering.

The new mainframe has "all of the capabilities of the z990 that we introduced last year, scaled down into a smaller size with a smaller price tag for our smaller enterprises," said Colette Martin, the director of zSeries product marketing with IBM.

Unlike the larger z990, which is powered by as many as four eight-processor "books" of CMOS processors, the z890 is a single-book system which can support up to four processors - "engines" in mainframe parlance. It is 30 percent smaller than IBM's other entry class mainframe, the z800, and like the z800 it does not require a raised floor to cool the system.

IBM hopes that the z890, which can be purchased with a processing capacity as low as 26 MIPS (million instructions per second), will appeal to companies looking to consolidate a large number of applications onto one system, or to those that are looking to better couple Linux applications with software that is running on the mainframe, Martin said.

To help broaden the zSeries' appeal, IBM will also unveil a specialized Java execution processor called the zSeries Application Assist Processor (zAAP) that is designed to speed up Java performance on the mainframe. As with IBM's Integrated Facility for Linux (IFL) processor, the zAAP is designed to make the zSeries suitable for a broader range of applications.

"Before this, WebSphere on the mainframe ate up a lot of standard engine cycles," Martin said. "Now those instructions are off-loaded to the zAAP engine and you can focus your standard processor on other work."

IBM also plans to announce a new scaled-down model of its Shark Enterprise Storage Server (ESS) array, called the ESS 750.

Ultimately though the z890 will have the greatest appeal for IBM's older System/360 and System/390 mainframe customers, said Charles King, a senior analyst with research company The Sageza Group.

"There are a lot of old-line mainframe customers who are maybe running one or two mainframes -- older boxes mainly to support legacy applications," he said. "IBM has been trying to come up with something that offers the price-performance that will bring those people into the zSeries world."

The z890 will be priced starting at $200,000 (£109,000) when it begins shipping on 28 May. The zAAP processor will be available on 30 June, priced at $125,000 (£68,000) per processor. The ESS 750 will ship in May, IBM said, and will be priced starting at $100,000 (£54,000).