"While there were signs of stabilization in the PC industry in key regions, including EMEA, Japan and Latin America, the relatively stable results were offset by the U.S. market, which saw a 10 percent year-over-year decline in part because of a very weak back-to-school sales season," said Mika Kitagawa, principal analyst at Gartner.

"Business PC demand, led by Windows 10 upgrades, continued to drive PC shipments across all regions, but its refresh schedule varies by region. The countries with stable economies, such as the U.S., have created a positive sentiment among businesses, especially for small and midsized businesses (SMBs), which are more vulnerable to external events, such as economic or political."

There are ongoing component shortages, with DRAM shortages getting particularly worse during the third quarter of the year compared with the first half of 2017. "The component price hike impacted the consumer PC market as most vendors generally pass the price hike on to consumers, rather than absorbing the cost themselves," Ms. Kitagawa said. "We expect the DRAM shortage to continue to the end of 2018, but it will not be reflected in the final PC prices immediately."

In the third quarter of 2017, HP Inc. and Lenovo were in a virtual tie for the top spot in the PC market based on shipments. However, HP Inc. is in an upward trend, as it has experienced five consecutive quarter of global PC growth, while Lenovo is in a downward trend with declining shipments in eight of the last 10 quarters.

HP Inc. experienced growth in all key regions, except the U.S. market. The company experienced double-digit growth in Latin America, while in Asia/Pacific HP Inc. secured positive growth for the fifth consecutive quarter. Lenovo experienced its steepest year-over-year decline of PC shipments in the U.S. since it acquired the IBM PC business division in 2005.

Lenovo continues to face the dilemma of market share gains versus profitability. It appears the company is putting more emphasis on profitability than share gain. Dell's worldwide PC shipments were slightly down compared with a year ago, as it registered its first year-over-year shipment decline since the first quarter of 2016.

In the U.S., PC shipments totaled 14.7 million units in the third quarter of 2017, a 10.3 percent decline from the third quarter of 2016. It was the fourth consecutive quarter of declining PC shipments.

"Weak back-to-school sales were further evidence that traditional consumer PC demand drivers for PCs are no longer effective," Ms. Kitagawa said. "Business PC demand is stable in the U.S., but demand could slow down among SMBs due to PC price increases due to component shortages."

PC shipments in EMEA totaled 19 million units in the third quarter of 2017, a 1.1 percent decline year over year. The contraction in the Western European PC market appears to have slowed down, with the potential for stability in the fourth quarter of 2017. Eastern Europe is experiencing flat to small unit declines as demand is not improving, and there is no obvious impact yet from the Windows 10 migration in the business segment.

In Asia/Pacific, PC shipments reached 24 million units in the third quarter of 2017, down 2.1 percent from the same period last year. While consumer demand remained lackluster, PC demand in the business segment remained steady, especially for notebooks. In China, the PC market is estimated to have declined by 5 percent in the third quarter of 2017, with more stability in the business market, particularly in large enterprises, than in the consumer space.

These results are preliminary. Final statistics will be available soon to clients of Gartner's PC Quarterly Statistics Worldwide by Region program. This program offers a comprehensive and timely picture of the worldwide PC market, allowing product planning, distribution, marketing and sales organizations to keep abreast of key issues and their future implications around the globe.