Unit sales fell 1.7 percent from a year earlier to 76.6 million, market researcher Gartner Inc. said Wednesday in a statement. IDC, another technology-research firm, said quarterly shipments worldwide fell 4.4 percent to 73.4 million.

The PC market is on course for a third annual contraction, threatening earnings at companies that rely on sales of the devices, such as Intel Corp. and Hewlett-Packard Co. One bright spot in the first quarter was an increase in business orders for desktop machines ahead of Microsoft Corp.’s end to support for its Windows XP operating system, Gartner said.

“While the PC market remains weak, it is showing signs of improvement compared to last year,” Mikako Kitagawa, an analyst at Gartner, said in the statement. In January, the Stamford, Connecticut-based researcher said PC shipments fell 6.9 percent in the fourth quarter, and 10 percent in 2013.

Shipments in the U.S. reached 14.1 million units, a gain of 2.1 percent from a year ago, Gartner said. In the Asia-Pacific region, units shipped were 24.9 million, down 11 percent. IDC said U.S. unit sales slipped 0.6 percent to 14.3 million.

Lenovo Leads

Lenovo Group Ltd. was the top vendor for the quarter, with global market share rising to 17.7 percent, IDC said. Hewlett- Packard was No. 2 with 17.1 percent, followed by Dell Inc. with 13.4 percent. All three grew from a year earlier at the expense of rivals Acer Inc. and Asustek Computer Inc. Acer’s shipments declined 20 percent, IDC said.

“We’re seeing a consolidation,” Loren Loverde, a researcher at IDC, said in an interview. “These top three are doing relatively well, but Acer and Asus are struggling because of their exposure to consumers.”

Last month, IDC projected PC unit sales will fall 6.1 percent this year — the third consecutive decline — to 295.9 million from 315.1 million in 2013. The research firm estimates the market will shrink through 2018.