Apple has updated its iMac line to include the new Intel Core 2 Duo processors and launched a 24-inch iMac.

The company claims its new processor offers up to 50 percent faster performance than before. Prices now start at $999.

"Every iMac-from the $999 model up through the new dazzling 24-inch wide-screen model now features blazing Core 2 Duo performance," said Phil Schiller, Apple's marketing head. "And the new 24-inch wide-screen 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 17-inch, a 2.16GHz 20-inch and the all-new 2.16GHz 24-inch iMac. The new 2.16GHz iMac costs $1,499.

The new 24-inch iMac features a 24-inch wide-screen LCD display with a 1,920 x 1,200 pixel resolution that offers 30 percent more screen space than the 20-inch model and a brighter display to make reading text and viewing images even easier. It includes a 2.16 GHz Intel Core 2 Duo processor with 4MB of shared L2 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. UK prices are not yet available.