San Francisco - US computer maker Dell is planning to sell its factories around the world to contract manufacturers within 18 months in a bid to save more than 3 billion dollars in costs, the Wall Street Journal reported Friday.

Most of the factories would be sold to manufacturers in low-cost Asian countries, who would then produce computers for the Texas-based company, the report said.

The move marks a drastic change to the business model that had propelled Dell to the spot of the world's largest-selling computer company before it was overtaken by Hewlett-Packard four years ago.

Dell had prided itself on its strictly-controlled production process and direct sales to customers. But the company now uses traditional stores to market its computers and lags behind competitors in using contract manufacturers to cut costs on ever-more popular laptops.

Last week the company reported disappointing quarterly profits, which sent shares falling more than 18 per cent.

The company owns factories in the US states of Texas, Tennessee, North Carolina and Florida, as well as in Ireland, India, China, Brazil, Malaysia and Poland, where it opened a plant early last year.

As their focus is on manufacturing, contract PC makers generally have more efficient processes than larger firms such as Dell, which must also balance marketing and other considerations.

According to the report, Hewlett-Packard, the world's largest computer company, outsources the production of some 50 per cent of its computers. Apple Inc has many of its PCs shipped directly from Asian manufacturers' plants to customers.