Apple updated its line of desktop computers on Tuesday with the latest-generation chips, as the company continues to gain share in the PC market.

Apple refreshed its all-in-one iMac line with new chips from Intel Corp and better graphics.

The iMac starts at £999 for a model with a 21.5-inch screen. The 27-inch version starts at £1,649. The new iMacs are available today.

The company also updated its high-end Mac Pro line with powerful quad-core and 6-core Xeon chips from Intel. The Mac Pro starts at £1,899 and will be available in August.

Apple also announced a new 27-inch LED display that will be available in September.

Apple sold 1 million desktop Mac units in its most recent quarter, up 18 per cent from last year, generating $1.3 billion (£834 million) in revenue.

According to industry tracker IDC, Apple ranks as the number four computer vendor in the United States, with an 8.8 per cent market share.

Shares of Cupertino, California-based Apple rose 1.3 per cent to $262.61 in morning Nasdaq trading.