Microsoft has become one of the top five PC vendors in the US.

Redmond's Surface devices helped it top Acer to become the country's fifth largest PC vendor by shipments in the third quarter, according to research firm Gartner, nabbing 4.1 percent market share on 602,000 shipments. However, Microsoft is still far behind No. 4 Apple, which shipped over three times as many units as Microsoft did for 13.7 percent of the market.

HP remained the top dog with a 30.7 percent share of the US PC market and 4.5 million units shipped.

The third quarter was the first time Microsoft cracked the top five rankings in Gartner's preliminary results for the US market, Gartner analyst Mikako Kitagawa told PCMag.

Technically, Microsoft was also a top five vendor in the last few quarters, but as Kitagwawa explained, "we underestimated Surface shipments in our preliminary results. But for this quarter, we believe that Surface shipments were high enough to declare their number five position. Thus, we were able to show them on our US top 5 ranking."

Globally, growth in the PC market was essentially flat. PC shipments were up by only 0.1 percent in the last year during the third quarter, according to Gartner.

Rival research firm IDC said shipment numbers actually shrunk by 0.9 percent year over year. Nevertheless, they still beat IDC's original forecast, which expected a 3 percent decline.

In the US, PC demand was given a lift by enterprises migrating from Windows 7 to Windows 10 and schools buying up Chromebooks for use in the classroom, IDC said.

But another driver has been consumers buying up PC gaming systems amid the rise of eSports, IDC analyst Neha Mahajan told PCMag. "Gaming is a massive draw right now," he said. "It's propping up the high-end of the consumer PC market."

The gaming demand and corporate refresh cycle promise to keep PC demand stable over the coming quarters. But challenges remain. An ongoing shortage of CPUs and brewing trade war between the US and China have sparked some fears that PCs and component costs may go up.

However, Mahajan doesn't expect consumers to end up paying any higher prices in the short-term. Vendors will try to absorb the costs from the CPU shortages, rather than risk losing PC sales, he said. The US tariffs on Chinese-made goods have also been confined to certain computer components, as opposed to fully assembled PCs from big-name brands.

"As long as the tariffs aren't on finished (PC) systems, which they aren't yet, we won't be experiencing a massive impact," he said. "Where I think things do start to get painful are for your local system integrators, who are doing a lot of the assembly in the US, and importing raw components."

Although Gartner ranks Microsoft as a top five PC vendor in the US, IDC does not since the research firm does not consider Surface devices to be PCs.

Editor's note: This story has been corrected to clarify Microsoft was also a top five PC vendor in the US market prior to this year's third quarter, according to Gartner's finalized PC shipment estimates.