Microsoft could soon add an all-in-one PC to its Surface lineup, filling a gap in the middle of a product range that spans from the svelte Surface Pro 4 tablet to the giant Surface Hub touch screen.

That's according to a rumor reported by ZDNet, which says that the new device will be marketed as a consumer version of the business-friendly Hub. Apparently code-named "Cardinal," the new all-in-one could come in a range of screen sizes from 21 to 27 inches.

Those sizes would position it well to compete with the Yoga Home 900, which currently dominates the niche market of large touch-enabled home PCs that are equally at home in the living room or kitchen as the office.

Rumors of such a device gained steam earlier this summer, when several publications reported that the all-in-one would sport an Intel "Kaby Lake" processor and go on sale by the end of 2016. ZDNet says the Cardinal will be announced at a hardware event Microsoft has planned for October. The company will also likely refresh its current line of Surface tablets, too.

One of the many unanswered questions about a potential Surface all-in-one is whether or not it would include a battery. The Yoga Home 900 does, though with around three hours of battery life, it can't stay unplugged for an extended game of chess or Monopoly. Family gaming is one area where large portable all-in-ones excel: the Yoga Home 900's kickstand collapses so it can be laid flat on a table to serve as a virtual game board.

A Microsoft spokesperson declined to comment on future plans for the Surface lineup.