The 10-inch diagonal screen has been the “default” size for the tablet computer screen since the introduction of the iPad three years ago. But Intel’s PC business leader says the de facto standard screen size for the tablet is on the way out.

Speaking at the company’s Intel Solutions Summit last week in Los Angeles, Kirk Skaugen, vice president and general manager of Intel’s PC Client group, said the 10-inch tablet is under pressure from both extremes. When it comes to standalone tablets, seven- and eight-inch screens are becoming increasingly popular, providing the full tablet experience in something with a size and weight more akin to an eReader. And for those who seek larger screen sizes, the current general of Ultrabooks provide a number of options, including 10- and 11-inch screens that are “detachable” from their notebook bases, and 13- to 15-inch screens that convert from an Ultrabook to a much larger tablet-type device.

While touch is increasingly becoming part of the Ultrabook design, Skaugen said that will be turned up to 11 later this year, when the next-generation Core processors for Ultrabook, codenamed Haswell, debut. Haswell promises more power for significantly less power consumption than current-generation processors. And Skaugen suggested a revision to the Ultrabook spec to coincide with the Haswell debut, one that would require touch screen capabilities.

To date, there have been interesting attempts at the “no compromise” PC that Intel foresees, one that seamlessly blurs the line between the notebook and the tablet. But so far, these machines all require too many compromises – on-board storage and battery life challenges are among the biggest complaints.

But if Ultrabook has taken the size and shape of the average PC and resulted in a significant change over the last two years, the chipmaker sees it making even bigger changes this year and into the future. CJ Bruno, vice president and general manager of Intel’s Americas business, noted that to date, the Ultrabook spec has been built around existing hardware roadmaps, meaning that the systems were largely built to suit the chips, which were already on the drawing boards when Intel debuted the Ultrabook concept. But he said that all changes this year, are the upcoming generation of Core processors are the first be designed with the Ultrabook in mind, shifting the mindset from chip-centric PC design to PC-centric chip design.

“This is where we re-invent the Ultrabook,” Skaugen said.

Skaugen predicted that by the holiday buying season, more than three quarters of Intel-powered PCs will be touch-enabled.

And while Intel hopes that these new Ultrabooks will drive some reverse cannibalization of the tablet market, it’s still got big plans for the existing standalone tablets that will exist. The company has made advances with both Windows 8 and Android-based tablets over the year, but Bruno concedes there’s still a lot of work to be done.

Skaugen provided an update on the company’s “Bay Trail” processors, due to debut later this year, which move to 22nm, quad-core chips that will more than double the processing power of the company’s current tablet offerings.

And while it’s fine with both Android and Windows 8 as a tablet platform, Skaugen subtly slammed the Windows RT platform from major partner (and Intel Solutions Summit sponsor) Microsoft. Skaugen said that having the Windows name on a product that doesn’t run the legacy Windows software stack was confusing for consumers, and that “even businesses have been surprised to learn that their Windows apps will not all work on Windows RT-based tablets.” He said more education is needed, and that the company’s slogan for Windows-powered tablets based on Windows 8 instead of Windows RT is simple “it just works.”

The company also restated its goal to get its chips in “billions of smartphones,” although it’s got a long way to go meet that goal. Still, citing early successes with Motorola and others, Bruno said that with the help of its channel, it can pull it off over the next few years.

“We believe that if it computes, it’s our business,” he said.