Apple has taken the third spot in U.S. PC sales for this year's second calendar quarter, in quasi-execo with Gateway, a recent IDC study claims.

Apple now holds 5.6% of the U.S. market up from 4.8% during the same quarter last year, or an increase of 26.2%. At the same time, Gateway saw a significant drop from 6.5% last year down to 5.6% during the last quarter.

As many as 960 000 computers have been sold by Apple this quarter in the U.S. while Gateway has sold 5000 more units.

Dell and HP remain leaders in the U.S. with, respectively, 28.4% and 23.6% of market share or 4.85 and 4.02 million computers sold in the U.S.

International top 5 figures published in the press release do not include Apple which appears to hold less than 4% of the worldwide market share.

Meanwhile HP leads worldwide with 19.3% of the market, Dell is down 4.9% to 16.1%, Lenovo holds 8.3%, Acer jumps 55.4% up and gets the fourth spot with 7.2% and Toshiba sees a slight increase to 4.1%% from 3.8% last year.

Apple has seen continuous sales upside in the PC segment since the transition of its computer line-ups to the Intel architecture, with progression rates well above the industry. Global PC shipments grew 12.5% this quarter, the study says.

The company is reporting its financial results next week. Analysts are expecting Apple to beat initial estimates and guidance on improved Mac sales, steady iPod sales and a slight inpact of the two first days of release of the iPhone.