May 3, 2011 12:54 GMT  ·  By

As rumored, Apple today updated its all-in-one iMac computers with next-generation quad-core processors, powerful new graphics, high-speed Thunderbolt I/O technology and a new FaceTime HD camera.

The system starts at $1,199 - the same as before - only the computer is now up to 70 percent faster, while the new graphics is said to deliver up to three times the performance of the previous generation.

Customers can get the base model with a quad-core Intel Core i5 processor or they can choose Core i7 processors up to 3.4 GHz.

The CPUs feature an integrated memory controller and a powerful new media engine for high-performance video encoding and decoding, Apple explains.

The graphics is AMD Radeon HD. On the standard configuration, it’s a 6750M graphics processor with 512MB of GDDR5 memory. On the most expensive iMac, customers get 6970M with 1GB of memory.

On the addition of a Thunderbolt port, Apple says the iMac is the first desktop computer to get one.

While the 21.5-inch configuration has a single Thunderbolt port, the 27-incher features two of them.

“Developed by Intel with collaboration from Apple, Thunderbolt enables expandability never before possible on an all-in-one computer,” Apple explains.

“Featuring two bi-directional channels with transfer speeds up to an amazing 10Gbps each, Thunderbolt delivers PCI Express directly to external high performance peripherals such as RAID arrays, and can support FireWire and USB consumer devices, and Gigabit Ethernet networks via adapters,” says the Mac maker.

Finally, the FaceTime HD camera now comes as standard on iMacs. To complement the new hardware, iMacs also come pre-installed with Apple’s 1-dollar FaceTime application.

“Our customers love the iMac’s aluminum enclosure, gorgeous display and all-in-one design,” said Philip Schiller, Apple’s senior vice president of Worldwide Product Marketing.

“With next generation quad-core processors, powerful new graphics, Thunderbolt technology and a FaceTime HD camera, we've made the world’s best desktop even better.”