Global shipments of personal computers bounced back in the third quarter of 2009, a sign that information technology spending will pick up in the coming months, a research group reported.

Back-to-school demand helped shipments to rise 2.3 per cent after falling for three consecutive quarters, according to research firm IDC's Worldwide Quarterly PC Tracker.

The market is expected to see double-digit growth in 2010, with desktop shipments roughly flat and portable computers driving overall increases in shipments.

"As commercial spending recovers in 2010, we expect to see robust growth over the next several years," said Loren Loverde, program director at IDC Worldwide Trackers.

Portable computers for consumers drove overall shipments in the third quarter and rose 33.5 per cent from 2008. Shipments of mini notebooks, or netbooks, designed for accessing the internet, surged to account for 28 per cent of portable shipments, from 14 per cent a year ago.

Those notebooks are expected to continue to grow at a slower rate than portable computers, since new ultra-thin portables are creating more competition in the market.