Overall, laptop reliability is improving gradually: 25.9 percent of respondents report experiencing at least one significant problem with their notebook, down from 30.9 percent last year and 31.8 percent two years ago.

When it comes to support, 1 in 5 desktop users (21 percent) report their problem was never resolved by the manufacturer; with laptops, the rate is slightly higher at 23.6 percent.

Apple laptops had another stellar showing in our survey. Apple desktop users gave the company above-average ratings in all five of our reliability measurements, and in all four of our service measurements. Apple laptops got above-average marks in all service measurements, and all but one reliability measurement: users say Apple laptops need components replaced about as often as other laptops do.

And when Apple customers do have problems, they’re generally satisfied with the company’s response. Just under 8 percent of Apple laptop users in our survey report their problem was never resolved by the company’s support team, significantly lower than the industry average.

Asus placed second to Apple and earned high marks for reliability of its portable PCs, and took high marks for its phone support. The vendor’s showing is a significant step up from its middling scorecard from last year, when Asus portable users reported a higher-than-average number of out-of-box problems. This year, Asus took above-average marks in five of eight measurements for laptop reliability and service, and its trouble with out-of-the-box problems seems to have improved.

Among Asus notebook users in our survey, 17.1 percent reported at least one major problem with their laptops--slightly higher than Apple’s 15.3 percent, but significantly lower than the industry average of 25.9 percent. (We discuss Apple and Asus further elsewhere.)

Toshiba laptops earned high marks for reliability once again this year, although readers rate its support as merely average. And MSI, which wasn’t in last year’s survey, made an impressive showing. Readers are satisfied with the notebook maker’s PCs, and report relatively few problems with core components.

HP, the largest seller of PCs in the US, disappointed again this year in the laptops category. HP laptops for home use showed up at the bottom of our rankings for both reliability, and HP came in last for their ability to support home laptops.

Dell, the second largest seller of PCs in the US, also earned poor marks for home laptops. Dell laptops ranked second to last, just above HP, for the reliability of their laptops.

We address HP and Dell’s dismal showing in more detail elsewhere.

As we did for desktops, we separated Dell and HP users’ responses for home laptops and business laptops, and found significant differences in their experiences.

Dell's professional laptop users report that support is relatively good at resolving problems, while its home customers say Dell's problem-solving skills are mediocre at best, for example. Similarly, the owners of Compaq and HP business notebooks seem far happier about the reliability of their machines the owners of HP consumer laptops.

Among HP consumer laptop users, 11.4 percent had a problem with a core component, such as the CPU, RAM, or hard drive, while only 7.2 percent of HP business customers did. (The industry average was 9.8 percent.)

Meanwhile, 21.6 percent of Dell home laptop users report their issue was never resolved by Dell support, a problem affecting only 13.6 of the company's business notebook customers. In Dell's defense, however, both of its home and business component-problem scores are better than the industry standard of 23.4 percent.

Click on the chart thumbnail at left to see our survey's findings on laptop reliability, by brand. For more on the measures used in the chart and the survey methodology, see "The Tech Brands You Can Trust."

After reading this article, you may want to jump to PCWorld's Facebook page, where readers can add their own stories of product reliability and vendor service.