IBM is joining the chorus of server manufacturers launching systems running on Intel quad-core Xeon processors.

It has introduced four rack servers and one blade server using the Xeon 5300, with starting prices ranging from $US2400 to just over $US3000.

A quad-core processor has four independent processors combined into one package, which allows the chip to perform four tasks simultaneously. Quad-core processors give the computer greater processing power than if it had dual-core or single-core processors. IBM said its x3650 server with a quad-core processor recorded a 64 per cent increase in performance compared to the same model running only a dual-core processor.

Quad-core technology makes it easier for IT managers to introduce virtualization into their data centers. Virtualization lets enterprises make better use of server capacity by running multiple programs -- and even different operating systems -- on the same physical server at the same time. IBM's quad-core System x servers support virtualization through a feature called IBM Virtualization Manager, which lets administrators manage virtual and physical servers on any number of virtualization software platforms, including VMware, Microsoft Virtual Server and Xen.

The new x3550 and x3650 were available for order from November. 14, and the x3400, x3500 and BladeCenter HS21 would be available in January, IBM said.

HP is scheduled to introduce new server models running the Xeon 5300 processor next week but is withholding product details until then. On Monday, Dell introduced server, blade and workstation computers using the quad-core design.

Intel's chief rival, Advanced Micro Devices, is expected to introduce its quad-core processors in mid-2007.