The worldwide personal computer market contracted sharply in the third quarter of 2012 (3Q12), with shipments declining over 8% from the third quarter of 2011, according to info from both the IDC (www.idc.com) and Gartner (www.gartner.com) research groups. Even Apple was affected, though less than everyone else.

According to IDC, Apple how has 12.5% of the U.S. personal computer market, though sales were down 7.5% year-over-year in the third fiscal quarter. Apple shipped approximately 2.1 million Macs during the quarter compared to just over 2.1 million in the year-ago period. Apple is now in third place among U.S. computer makers.

The top five companies in the market — according to IDC — are HP (26.1% market share, down 18.8% year-over-year with sales of approximately 4.2 million), Dell (20.7%, down 16% year-over-year with sales of 3.4 million), Apple, Lenovo (8.3%, with sales of 1.4 million, up 9.2% year-over-year) and Acer (6.7%, with sales of about one million, down 8.5% year over year).

According to Gartner, Apple how has 13.6% of the U.S. personal computer market, though sales were down 6.1% year-over-year in the third fiscal quarter. Apple shipped approximately 2.1 million Macs during the quarter compared to just over 2.2 million in the year-ago period.

The top five companies in the market — according to Gartner — are HP (27% market share, down 19.3% year-over-year with sales of approximately 4.2 million), Dell (21.4%, down 16% year-over-year with sales of 3.3 million), Apple, Lenovo (6.1%, with sales of 1.4 million, up 6.1% year-over-year) and Acer (6.5%, with sales of 989,725, down 28% year-over-year).

The top five computer vendors worldwide, as determined by both IDC and Gartner, are HP, Lenovo, Dell, Acer and ASUS.