Apple has updated its entire iMac line with new Intel Core 2 Duo processors in every model and added a new 24in iMac.

The company claims its new processor offers up to 50 percent faster performance than before. In the US, iMac prices now start at $999 (about £530).

"Every iMac – from the $999 model up to the new dazzling 24in widescreen model – now features blazing Core 2 Duo performance," said Phil Schiller, Apple's senior vice-president of worldwide product marketing. "And the new 24in widescreen iMac is the fastest, biggest and brightest iMac we've ever made."

The new iMac lineup includes four models: a 1.83GHz and a 2.0GHz 17in, a 2.16GHz 20in and the all-new 2.16GHz 24in iMac.

The new 20in 2.16GHz iMac costs $1,499 (£796) in the US. Features remain the same, except the model now includes a 2.16GHz Intel Core 2 Duo processor. The 17in iMac now costs from $999 and features either a 1.83GHz or a 2.16GHz Intel Core 2 Duo processor.

The new 24iin iMac features a 24in widescreen LCD display with a 1,920x1,200 pixel resolution that offers 30 percent more screen space than the 20in model and a brighter display.

It includes a 2.16GHz Intel Core 2 Duo processor with 4MB of shared Level 2 cache, 1GB of 667MHz DDR2 SDRAM memory, a 250GB Serial ATA hard drive, nVidia GeForce 7300 GT graphics with 128MB of GDDR3 memory and a SuperDrive.

A 2.33GHz Intel Core 2 Duo processor is available as a build-to-order option.

The 24-inch model costs $1,999 (£1,061) in the US. Its features include:

  • 1GB of 667MHz DDR2 SDRAM expandable to 3GB;
  • an 8x SuperDrive with double-layer support (DVD+R DL/DVD+/-RW/CD-RW);
  • PCI Express-based nVidia GeForce 7300 GT with 128MB GDDR3 memory;
  • built-in iSight video camera;
  • AirPort Extreme and Bluetooth 2.0+EDR;
  • AirPort Extreme and Bluetooth 2.0+EDR;
  • a 250GB Serial ATA hard drive running at 7,200 rpm;
  • Mini-DVI out (adapters for DVI, VGA and Composite/S-Video sold separately);
  • built-in stereo speakers and microphone;
  • and an infrared Apple remote, Mighty Mouse and keyboard.

UK prices will be published when available.