
The study noted that the quarter's 9.8 per cent growth was slower than in recent quarters, but pointed out that total PC shipments exceeded 52 million units.
IDC expects the second half of 2006 to be strong enough to maintain double-digit growth for the year.
The analyst firm found that PC shipments in western Europe and Japan were " considerably slower" than expected in the second quarter, largely due to short-term factors such as inventory reduction and the World Cup.
Growth in Asia/Pacific, excluding Japan and Rest of World (including Latin America, Canada, central and eastern Europe, and Middle East and Africa) was down slightly from the prior quarter, but still ahead of expectations. Growth in the US rose slightly from the first quarter.
"Mature regions, like the US, western Europe and Japan, are exhibiting more conservative growth trends, while developing regions are not only growing faster, but exceeding expectations," said Loren Loverde, director of IDC's Worldwide Quarterly PC Tracker.
"Although this is an important development trend, it is also the case that the bulk of portable PC adoption - the leading market driver - remains concentrated in the more mature markets.
"As a result, there is plenty of opportunity for PC companies to grow, but they need to adequately target the growth segments in each region."
In light of the 2Q06 results, IDC's growth projections for 2006 were lowered slightly from the June forecast.
However, volume predictions for 2007 remain unchanged and future years have been bolstered by the strong outlook in emerging markets as well as further growth potential driven by new product designs and digital convergence.
"We believe that consumer notebooks will continue to drive strong overall PC sales through the rest of this year despite the presence of many potential competitors for discretionary income this holiday season, such as flat-panel TVs," said Bob O'Donnell, vice president of clients and displays at IDC.
"Looking forward, we expect that desktop shipments will begin to stabilise, particularly in the enterprise segment. However, consumer notebook adoption will fuel industry growth and move us closer to the day when notebooks will out-ship desktop PCs."