"We are seeing a shift in the computing world to more powerful mobile computing solutions, " said SY Shain, senior vice president of ASUS' notebook business unit.

ENGADGET: Western Digital builds 5mm-thick hybrid hard drive, Ultrabook makers sign on early

"Because all-in-ones integrate a desktop tower into the back of a flat-panel display, they typically use smaller, less powerful notebook components that don't require a lot of space, " said Steve Smith, senior business manager of consumer desktops, Acer America.

ENGADGET: Gateway brings ZX4300 and ZX6900 all-in-one touchscreen PCs into a world of fingers