As promised by the company earlier in the week, and by Tim Cook at the last Apple launch event, the new iMac has gone on sale, with dispatch currently promised for within three days of purchase.

First out of the blocks is the 21.5-inch version, with the 27-inch iMac coming in the next few weeks. Two basic models of the smaller edition are available, with slightly different Intel Core i5 processors, Turbo Boost options and graphics processing.

Read: Apple iMac (2012) pictures and hands-on

The 2.7GHz version starts at £1,099, while the moderately better specified 2.9GHz model costs from £1,249. Both of them, like the 27-inch version too, feature superslim waistlines thanks to Apple's adoption of a friction-stir welding process.

According to the manufacturer, this "uses a combination of intense friction-generated heat and pressure to intermix the molecules of the two aluminium surfaces - creating a seamless, precise and superstrong join".

The 21.5-inch new iMacs are available to order through the Apple online store now.

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