Lenovo is posing a serious challenge to the long-standing top spot of HP in the PC market.

Pushed by strong growth in its PC shipments, Lenovo moved ahead of Dell in the third quarter and began mounting an attack on HP's lead, according to a report from IHS iSuppli.

It's an impressive move for a company that was in fourth place as recently as the first quarter of this year.

Despite the fact that the overall PC market only grew by 5.5% in Q3, Lenovo came on strong, showing 14.5% growth and going from 10.9 million shipments in the previous quarter to 12.5 million in the third.

Lenovo now accounts for 13.9% of all global PC shipments - just 4.2% below market-leader HP.

That's a tighter horse race than HP has been used to in recent years. According to iSuppli, Lenovo's challenge represents the closest any PC maker has come to taking the lead position from HP since the second quarter of 2008, when Dell came within 2.7%.

"Lenovo continues to capitalise on strong demand for PCs in its home market of China," Matthew Wilkins, a principal analyst iSuppli, said. "While PC sales in the United States, Europe and many other regions are suffering because of weak economic conditions and rising competition from media tablets, desktop and notebook sales remain red hot in China. This is allowing Lenovo to outgrow its US rivals, and putting it in position to contend with HP for market leadership."

Today's report from iSuppli echoes data industry analyst firm Gartner put out in October.

Gartner noted last month that Lenovo had surged in the third quarter to take over the second-place spot from Dell, largely crediting Lenovo's "aggressive marketing" in both the enterprise and consumer markets for the company's move.

HP may be ripe for a challenge with the turmoil it stirred up this fall.

In August, HP announced that it was considering spinning off its PC manufacturing business. And while HP reconsidered and decided to keep the business, the possibility created a stir in the industry.

Dell CEO Michael Dell later said the confusion that HP caused in the industry created an opportunity for other PC manufacturers.

"Any uncertainty or confusion that exists is an opportunity," Dell said at the Web 2.0 Summit in San Francisco in October. "No question we've seen significant opportunities from what is going on over there at HP. Customers think about what is going to happen in a year or two and that erodes their confidence."