Apple’s new operating system for Mac computers goes on sale today, slightly earlier than expected, as the company seeks to continue expanding its share of the PC market.

Apple’s new Snow Leopard software will sell as an upgrade for €29. The company had previously said it would ship in September.

Apple sold 2.6 million Mac computers in the June quarter, up 4 per cent from a year ago.

The company is the fourth- biggest PC maker in the US, according to research group Gartner, with 8.7 per cent of that market.

It does not rank in the top five in global shipments.

Apple rival Microsoft’s new Windows 7 operating system is due in October. – (Reuters)