Despite slipping from first to third in the UK PC market in 2009's second quarter, HP could soon be back on top, according to IDC.

Preliminary figures published by the market watcher this month revealed Dell was the UK's top PC vendor last quarter with a 24.4 per cent market share. Acer grew shipments by 37 per cent year on year to grab second spot with a 21.3 per cent slice of the market.

HP's shipments slumped by a quarter, leaving it third with a 17.4 per cent share. Acer's performance was fuelled primarily by the consumer market, where the success of its netbooks gave it top spot in the notebook space. It also dominated the consumer desktop arena, with its 31.5 per cent market share more than that of HP and Dell combined.

IDC research manager Eszter Morvay said: "Acer's performance is so strong in the consumer space and they have also always been very strong in the SME area, where they have deployed aggressive pricing.

"But it does not have a footprint in the corporate space. Once the economic climate is better and the renewal cycle starts we will see different results for HP and Lenovo. Dell and HP cover the whole market, but Acer's market level will be capped."

Morvay added that the economic climate had made the market fluctuant and claimed HP was more than capable of being back on top next quarter. "The current market is incredibly volatile," she said. "When the market was growing it was a lot more predictable."

Such volatility is illustrated by the performance of Asus, which more or less invented the netbook market with the launch of its Eee PC. The product's success drove the Taiwanese manufacturer to become one of the notebook market's biggest players. But Asus is now languishing in ninth spot in the UK laptop market.

Morvay explained: "Two key areas have really hurt Asus: it has been battling with inventory on the one hand and competition on the other. It has had some inventory issues, including a major deal with Carphone Warehouse, which burned its fingers. And it may have invented the netbook category, but Acer and Samsung have launched major pushes."

The volume of desktop shipments in Q2 continued to spiral downwards, falling 24 per cent year on year. Morvay predicted the market could pick up a little as the economy recovers, but that desktop sales would ultimately continue their negative trajectory.

"Desktop volumes have been declining steadily for the past three years," she said. "Once the economic climate improves, companies will reinvest in IT infrastructure and corporate desktop demand will creep up. But, overall, desktop volumes will steadily decline over the next five years. The key problem is cannibalisation by notebooks – they are two competing technologies."