Dell XPS 13 Ultrabook sales are exceeding expectations, the company says.

Spearheaded by chipmaker Intel, Ultrabooks are Windows PC manufacturers' response to Apple's popular MacBook Air, a slim-and-light laptop that replaced the venerable hard disk with solid state (SSD) storage, and eliminated the seldom-used DVD drive altogether.

The Ultrabook strategy appears to be working, at least for Dell. Sales of the XPS 13, which debuted at the end of February, are twice what the company had originally forecast, Dell product marketing director Alison Gardner tells Reuters.

Dell has refocused its efforts on the enterprise market in recent years, and nearly half of the XPS 13 sales have been to corporations, Gardner says. The company declined to provide Reuters with exact sales figures.

PC vendors are expected to ship many more Ultrabooks this year, according to Intel. Some analysts believe Ultrabooks will face serious competition from tablets, which may be better suited to consumer and corporate users with basic computing needs.