PC vendors reported global shipment growth of 12.5 percent in the second quarter as every major vendor except Dell posted a double-digit percentage increase in unit shipments compared to the same period last year, according to a report released Wednesday by IDC.

Dell shipped 4.9 percent fewer PCs during the quarter than it did in 2006 as the company continued to struggle with a corporate restructuring effort that has included deep job cuts, changes in executive leadership, and a new strategy of selling computers through retail channels instead of only online.

In contrast, Hewlett-Packard Co. (HP) consolidated its position as the world's largest PC vendor with unit shipment growth of 36.5 percent. Overall, vendors sold 58.8 million PCs in the quarter, IDC said.

A report released on the same day by Gartner showed similar results with Dell sliding 5.5 percent compared to HP's growth of 36.6 percent. Gartner reported that global PC shipments rose 11.7 percent to 61.1 million units.

HP is seeing good results because of a multifaceted approach that allows the company to concentrate its sales efforts on new regions if sales slump in another sector, said David Daoud, manager of the personal computing and PC tracker programs at IDC.

"They are not putting all their eggs in a single basket," he said. "That is the result for a company that has adopted a multifaceted approach. PC shipments were slightly better than expected in the U.S., but they have done even better outside the U.S. in emerging markets and western Europe. So they can manage multiple regions."

Despite the contrast in trends, none of the top five vendors changed their worldwide rankings by market share. For the quarter, HP claimed the top spot with 19.3 percent of global PC sales volume, leading Dell with 16.1 percent, Lenovo with 8.3 percent, Acer with 7.2 percent and Toshiba with 4.1 percent, according to IDC. The Gartner study showed the same rankings.

However, Acer could soon begin to climb the rankings, if its success continues. The company improved its PC shipment volume by 55.4 percent in the second quarter, pulling close behind Lenovo, which grew at 22.3 percent.

"Acer is laser-focused on particular segments, especially SMB and channel resellers," Daoud said. "They are just plowing."

In the U.S., Acer is only the sixth-biggest PC vendor but showed the fastest rise in shipments, improving by 163.8 percent over the second quarter of 2006.

Overall, the U.S. market is lead by Dell with 28.4 percent market share by shipments, then HP with 23.6 percent, Gateway and Apple with 5.6 percent each, Toshiba with 5.3 percent, and Acer with 5.2 percent. IDC counts PC shipments including sales of desktops, notebooks, ultraportables, and x86 servers, but not handhelds.

Overall, the global market achieved its 12.5 percent shipment growth in the quarter thanks to good activity in the Asia-Pacific region and to slightly better than expected activity in the U.S., Daoud said. That growth rate was higher than the first quarter, when shipments rose 10.9 percent over that period in the previous year, and higher than the second quarter of 2006, when shipments rose 9.7 percent year on year.

For the future, consumers continue to buy notebooks instead of desktops as the cost premium between the two models has narrowed to its smallest differential yet. IDC forecast strong growth in the second half of 2007 but said that market competition will be more complex than just cutting prices. Instead, PC vendors will try to get customers' attention with system design, customer service, channel coverage, and market expansion.