In less than a week, Hewlett-Packard, Dell and Lenovo have all rolled out new low-cost, ultraportable notebooks. The move by three of the world's largest PC vendors shows the growing impact low-cost laptops have had on the overall PC market, especially as these companies look to increase sales in a slowing market.

While these low-cost notebooks, or "netbooks," were originally envisioned as laptops for schoolchildren or cheap alternatives for users in emerging markets, these notebooks have actually helped the PC industry keep its sales going as enterprises continue to hold off on refreshing their PC fleets.

Recent reports from IDC and Gartner show that these low-cost laptops helped overall PC shipments grow by about 15 percent in the third quarter of 2008, despite the looming financial crisis and the worry that businesses, especially in the financial sector, will begin to curtail hardware spending in 2009. Earlier in 2008, IDC revamped its estimates, and it said it now believes shipments of low-cost notebooks could top 10 million units by the end of 2008.

Click here for the specs of the new Lenovo IdeaPad S10e. 

The release of low-cost notebooks from HP, Dell and Lenovo the week of Oct. 27 also shows how the three companies are adjusting the form factor of these laptops to meet the needs of all types of customers. Dell offers a 12-inch screen and HP and Lenovo now offer netbooks with 10-inch displays, which makes these laptops ideal companions for workers who travel several times a week and do not wish to drag a full-sized, 5-pound notebook through the airport.

At a Gartner symposium earlier in October, analyst Leslie Fiering told eWEEK that the first crop of netbooks, such as Asustek Computer's Eee PC, had 7-inch displays that limited the laptops' business use. These newer notebooks offer larger screens—8.9-inch to 10.2-inch—that allow for a full Microsoft Windows experience.

"When the first Asus came out, people were attracted to that small, small price but they felt it was not practical for them," Fiering said. "So now you are seeing a lot of the new products come out with a 10-inch display. When we talk about where the natural break points are when it comes to screen size, 10-inch and a possible 8.9-inch is the lowest screen size where you can comfortably use a full desktop Windows [image]."

The HP Mini 1000 series, which debuted Oct. 29, offers users a choice of either an 8.9-inch or a 10.2-inch display, which should allow for the full Windows or Linux experience. The revamped Lenovo IdeaPad S10e also has a 10.1-inch display and offers the choice of either Windows XP or SUSE Linux Enterprise.