How to buy the perfect laptop

It wasn't so long ago when the basic decisions you had to make when buying a laptop were how much you were willing to spend, the screen size, weight, chip power, and internal storage. Now it just begins with form factor.

Check out this gallery of advice based on a post by Joshua Goldman, and Craig Simms, of CNET Australia that will help make your decision a lot easier.

1. Choose your form factor

We break notebooks down into five categories by weight, with some overlap: netbooks (usually less than 2.2lbs.), ultraportables (3.3lbs.-4.4lbs), thin and lights (2.2lbs-3.3lbs, mainstream models (4.4lbs-8.8lbs) and desktop replacements (generally 8.8lbs or heavier).

New netbooks are rare things, but you can still get one if you really try. They were effectively killed off by the price drop of considerably more powerful mainstream laptops, the MacBook Air 11 and ultrabooks bringing portability at a good price.

These days, you can pick one up for under US$300, but we'd advise you to steer clear; there are simply better options and experiences available now.

While there are still a few ultraportables around, like Sony's Vaio Z series and Alienware's M11x R3, they have effectively been killed off by thin-and-light laptops, or what Intel calls ultrabooks. Occupying the 11- to 13-inch space, thin-and-light laptops can now genuinely claim extra portability with minimal performance sacrifice. Going for between US$999 and US$2300 depending on build quality, storage capacity, aesthetics and branding, thin and lights are the natural evolution of the category defined by Apple's MacBook Air. Don't expect optical drives here, but battery life in this category is generally excellent.

Mainstream laptops are like budget desktops; they're good for general tasks, but they won't win any contests for their performance. They're significantly thicker than the newest thin-and-light laptops to hit the shelves, but typically come with more ports and generally have more powerful processors and dedicated graphics cards, usually at the detriment to battery life.

This category is set for a shake-up in 2012, with many analysts expecting things to get thinner — whether this is at the sacrifice of ports remains to be seen.

If you want desktop power, you need a desktop replacement. With screen sizes of 16- to 18-inches, weight as heavy as 6 kilograms and average battery life of less than three hours, these behemoths are not for people on the go. They can accommodate a wide range of performance parts, however, and are just right for power users of all kinds.