Promising systems that are significantly faster than the current generation Macs, Apple chief executive Steve Jobs has unveiled the first iMac computers and MacBook Pro notebooks running on Intel Core Duo processors.

Apple first announced the switch from Power chips to Intel processors last year at the Worldwide Developers Conference, promising to ship the first Intel products before June 2006.

"It's not a secret that we've been trying to shoehorn a [Power] G5 into a PowerBook," Jobs told delegates at Macworld in San Francisco as he unveiled the MacBook Pro.

The performance per watt of the Intel chip was the main reason for Apple to switch to the Intel platform, Jobs said.

The MacPower Pro is the successor to the PowerBook notebook. It comes with a 15.4in screen and either a 1.67GHz or a 1.93GHz Intel Core Duo processor.

The new models offer a four- to five-fold performance increase, Jobs claimed. They are selling at $1,999 and $2,499 respectively, and will be made available in February. Apple is taking pre-orders now.

Jobs also unveiled a new iMac powered by a Intel Core Duo processor. Promising a two- to three-fold performance increase, the computers come in a 1.83GHz 17in model and a 2GHz model with a 20in screen. They will be priced identically to the existing iMacs at $1,299 and $1,699 respectively.