Meanwhile, International Data Corp (IDC) said shipments fell 10.8 percent to 71 million units.
Up to Thursday's close, the dollar had risen about 5.6 percent this year against a basket of major currencies.
Gartner also said the Windows 10 launch in the quarter had minimal impact on shipments as users chose to upgrade to Windows 10 on existing PCs.
Gartner said analysts "see some signs for future stabilization and growth" in the PC market. The firm said in July that it did not expect the global PC market to recover until 2016.
"The PC market continues to contract as expected, but we remain optimistic about future shipments," said Jay Chou, research manager at IDC Worldwide PC Tracker.
Gartner last month said the combined desktop and mobile PC market in India totalled nearly 2.2 million units in the second quarter of 2015, a 13 percent decrease over the second quarter of 2014, according to a report by market research firm Gartner.
American global IT major Hewlett-Packard (HP) still maintained the top slot with 26.3 percent market share despite showing a decline of 6.1 percent. It had recorded 29.4 percent market share in the second quarter of 2014.
"Consumers accounted for 48 percent of total PC sales in the second quarter of 2015," said Gartner research director Vishal Tripathi.
Written with agency inputs
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