Shipments of notebook PCs surged nearly 40 percent to 38.6 million units, while desktop shipments fell 1.3 percent to 38.5 million.
Overall, PC shipments rose 15.4 percent in the quarter to 79 million units.
Acer Inc shipped almost 3 million more notebooks in the third quarter than in the previous quarter, with the majority being netbooks, iSuppli said. The Taiwanese company is now the third largest PC company by market share at 12.2 percent, less than two percentage points behind second-place Dell Inc.
Hewlett-Packard Co maintained its lead at No. 1, shipping 14.9 million units for an 18.8 percent market share.
Apple Inc lost nearly half a point of market share from the second quarter. The company's 3.2 percent share places it seventh overall in total shipments.
ISuppli raised slightly its 2008 unit growth forecast. It now expects 13 percent growth this year, up from its previous 12.5 percent forecast.
For 2009, the group expects unit growth of 4.3 percent.
