The analyst firm estimates that HP's PC sales were up by nearly a quarter, giving it a market share of 17.4 per cent. Dell's sales fell by nearly nine per cent, leaving it with 13.9 per cent of the market.
"Dell's market share was its lowest in four years. It lost market share across all segments in the US, particularly the home market," said Mikako Kitagawa, principal analyst for Gartner Dataquest's Client Computing Markets Group.
"The fourth quarter's consumer bias favours HP, but Dell's accelerated shipment decline in the fourth quarter is surprising."
Worldwide PC unit shipments in the fourth quarter of 2006 grew 7.4 per cent compared to a year ago, reaching 67.3 million units.
Worldwide PC sales totalled 239 million units in 2006, a 9.5 per cent increase on 2005. EMEA continued to be the largest PC region during the year.
Asia/Pacific and Latin America showed strong growth, but US PC shipments were well below the average, reflecting the maturity of the market, according to Gartner.
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