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Sources reveal specs of Apple's iMac refresh

Apple on Tuesday will update its iMac line of desktops, with both the 21.5-inch and 27-inch models receiving processor speeds ranging from 3.06GHz to a 2.8GHz quad-core model.

According to a person familiar with the matter, Apple on Tuesday will introduce four new iMac models. Currently, its online store is down in anticipation of new products.

The 21.5-inch iMac desktop will be offered with 3.06GHz and 3.2GHz processors, as well as 4GB of RAM standard. The 27-inch models will come with 3.2GHz of speed, and a 2.8GHz quad-core processor. Both of the big-screen iMacs have 4GB of RAM as well, and a standard 1TB hard drive.

The details of the new models are:

MC508LL/A - IMAC 21.5"/3.06/2X2GB/500GB/4670/SD-USA
MC509LL/A - IMAC 21.5"/3.20/2X2GB/1TB/5670/SD-USA
MC510LL/A - IMAC 27"/3.20/2X2GB/1TB/5670/SD-USA
MC511LL/A - IMAC 27"/2.8QC/2X2GB/1TB/5750/SD-USA