Tablets were once hailed as laptop killers. Within just a few years, the tablet market grew from nothing to selling over 200 million units a year, cannibalizing the laptop market in the process. Both Microsoft (NASDAQ:MSFT) and Intel (NASDAQ:INTC), the stalwarts of the PC, were left behind as sales weakened.

The post-PC era, however, has yet to materialize. Tablet sales have slowed dramatically, and IDC predicts a flat tablet market in North America and Western Europe in 2014, a far cry from the 25% growth those regions saw in 2013. At the same time, the PC market has stabilized, and Gartner reported that PC shipments actually grew during the fourth quarter to 83.7 million units.

While the past few years have been defined by the incredible rise of mobile devices, the big story in 2015 will be the resurgence of the laptop, a form factor with some new tricks up its sleeve thanks to Intel's Broadwell processors and surprisingly, Microsoft's Windows 8. Some of the most exciting devices unveiled at the recent Consumer Electronics Show were laptops, and that's good news for both companies.

Thin, light, and fast
Intel's Broadwell processors mark the company's move to a 14-nanometer manufacturing process, a more advanced technique that allows for better energy efficiency. Intel claims battery life will improve by 20% to 30% over the previous generation of processors, and graphics performance will increase as well.

Lenovo LaVie Z. Source: Lenovo

Broadwell's benefits can be seen in the types of devices shown off at CES. Lenovo, the largest PC vendor in the world, unveiled the LaVie Z, the world's lightest 13-inch laptop. At just 1.72 pounds, the LaVie Z easily bests Apple's 13-inch MacBook Air which weighs in at 2.96 pounds. A slightly heavier version with a touchscreen will also be available, allowing the device to be used much like Lenovo's Yoga line of convertible laptops.

Dell XPS 13. Source: Dell

Dell showed off its new XPS 13, also featuring Broadwell and what the company is calling an "infinity display." Dell has removed nearly all of the bezel that typically surrounds the screen, allowing the company to squeeze a 13-inch laptop into a much smaller frame. The result is what Dell refers to as the smallest 13-inch laptop on the planet, although it's quite a bit heavier than Lenovo's LaVie Z.

Asus, which previously had success with its Transformer Book T100 two-in-one, unveiled a larger, more powerful variant called the Transformer Book Chi. There are three versions of the Chi, with the high-end T300 using Intel's new Core M processor, a version of Broadwell with extremely low power usage aimed at fanless two-in-ones. Core M has allowed Asus to make the T300 thinner than a MacBook Air and twice as powerful as an iPad Air, all with eight hours of battery life.

Asus Transformer Book T300 Chi. Source: Asus

The trend is clearly toward thin, light, and versatile machines. Broadwell provides the horsepower while sipping battery power compared to previous generations, and Microsoft Windows 8 enables convertible and two-in-one devices to work well as both laptops and touch devices.

Wintel makes a comeback
Initially missing the boat on tablets, Intel has been busy subsidizing its low-end Atom chips in order to win market share. Similarly, Microsoft started giving away Windows for small devices to lower prices and spur demand. Needless to say, both companies are welcoming PC sales growth with open arms.

Before Broadwell, Intel had Atom processors for low-end tablets and two-in-ones and Core processors for higher-end devices such as the Microsoft Surface Pro 3. Core M fills the gap between those two extremes, and it should result in a wider range of price points over the next year. Intel should benefit not only from increased laptop sales, but also by providing midrange alternatives to low-end Atom-powered devices.

And despite the problems with Windows 8, real or perceived, the operating system is far more versatile than either Android or iOS, and the upcoming Windows 10 release should address many of the issues people have with the current version. Microsoft's decision to build an OS capable of both a traditional desktop and touchscreen interface is ultimately what has enabled the wide range of laptop form factors we're seeing today.

This versatility, combined with the efficiency and performance of Intel's Broadwell, has created an environment in which laptops are once again appealing to consumers. Tablets are simply unable to match the productivity features of laptops, and we are seeing that reality in stagnating tablet sales.

The PC market has the potential for a great 2015. It will be driven by thin, light, and fast devices, spread across the full spectrum of price points. The release of Windows 10 later this year should be another tailwind, possibly prompting those still using Windows 7 to finally upgrade their hardware. They'll certainly have plenty of options to choose from.