Apple said on Tuesday it is updating its iMac and Mac mini desktop line of personal computers with prices starting at $599.

The new line of desktop computers includes a 24-inch iMac with twice the memory size and twice the storage of the previous generation 20-inch iMac, but is priced at the same$1,499. The new iMac line includes one 20-inch PC and three new 24-inch iMacs priced between at $1,199 to $2,199.

The 20-inch model is powered by a 2.66 GHz processor, while the 24-inch iMac has processor speed options of 2.66 GHz, 2.93 GHz (for $1,799), or 3.02 GHz (for $2,199). It comes with a 640GB hard drive and 4GB of RAM expandable to 8GB; the 20-inch comes with a 320GB hard drive and 2GB of RAM expandable to 8GB. (See: The new updated iMac has faster processor and high-performance graphics)

"Our flagship 24-inch iMac with twice the memory and twice the storage is now available for just $1,499," Apple chief operating officer Tim Cook, currently standing in at the helm of the company in place of iconic CEO Steve Jobs, said in a release.

As for the new Mac Mini, the big upgrade is NVIDIA GeForce 9400M integrated graphics that Apple says will improve its graphics performance as much as fivefold. The monitor-free machine costs either $599 for a lower-end edition (1GB RAM, 120GB hard drive) or $799 for the higher-end (2GB RAM, 320GB hard drive).

"The Mac mini is not only our most affordable Mac, it's also the world's most energy-efficient desktop computer," said Jobs.

The company also introduced a new Mac Pro desktop PC aimed at business users. The new Mac Pro starts at $2,499 for the quad-core model, $300 less than the previous Mac Pro, and goes up to 3,299 for the eight-core version.