Apple UK is shipping its rack-mount server Xserve.

The company has racked-up 4,000 pre-orders for the servers since its May debut.

According to Apple, performance tests show Xserve outperforms more expensive, similarly configured server offerings in Web serving and disk performance.

Phil Schiller, Apple's senior vice president of worldwide product marketing, said: "Xserve's G4 processing power, massive storage, incredible I/O performance and Mac OS X Server software with unlimited-client licences are making it a hit with customers who want an affordable, powerful 1U rack-mount server."

Apple offers services and support programmes for Xserve, including four-hour on-site response, 24-hour, seven-days-a-week technical support, AppleCare Service Parts Kits and the AppleCare Professional SupportLine and Tools programme.

Xserve is available in the UK through the Apple Store and Apple Authorised Resellers.

The Xserve is available in two standard configurations of either 1GHz PowerPC G4 processor and 256MB DDR RAM for £2,212 or dual 1 GHz PowerPC G4 processors and 512MB DDR RAM for £2,978. There is also an option to customize the machine (prices exclude VAT).