Lenovo's IdeaCentre Horizon may fit our definition of an all-in-one PC, but it's sufficiently different to enter a class of its own: that of table PC.
Marketed as a "table PC", the 27in IdeaCentre Horizon is part desktop PC, part tablet PC. A small stand allows it to sit on a desk, much like any other all-in-one, but folding this away enables it to function like a massively oversized tablet. Just like a tablet, it comes with a built-in battery which ensures that you can use it away from mains power, albeit for only a couple of hours.
Loaded with Windows 8, it's the additional bundled software which transforms it into a device that's designed to be used horizontally on a table top. Lenovo's "Aura" environment, provides a simple touch-enabled environment which is designed to be used from any angle so multiple users can operate from all sides while sitting around the device.
A selection of games are included, with a strong multi-user bias, turning the device into a sort of high-tech compendium of family board games. Just like board games, some of these make use of physical objects which interact with the 'board'. These include four hand-held "strikers" for a game of virtual air hockey, mini joysticks and a Bluetooth-enabled die for on-screen Monopoly japes. See also Group test: what's the best all-in-one PC?
Lenovo IdeaCentre Horizon: all-in-one PC, and a tablet
It's these gadgets and pre-loaded software which really make all the difference with the Horizon, enabling casual, tablet-style use without the need to delve into the Windows 8 operating system.
More fun and educational titles can be downloaded, not only from the Windows Store, but also Lenovo's own App Shop. Many Android apps are also available, thanks to the pre-installed BlueStacks App Player.
Connectivity options are somewhat restricted. There are only two USB ports, which really isn't enough – especially as one of these is taken up by an RF receiver for the supplied wireless keyboard and mouse. You get an HDMI input, so you can hook up a Blu-ray player or games console, but no HDMI output to power an external screen or projector. There's also a handy media card reader built in.
The display is a glossy IPS touchscreen with a standard HD resolution of 1920 x 1080 pixels. It's great for watching videos and delivers excellent contrast, but can't match the pro-level clarity or colour reproduction of the Apple iMac or Dell XPS 2720 all-in-one PCs.
Our review system came fitted with a 2.0GHz Intel Core i7-3537U dual-core processor which is powerful enough, but let down by the sluggish performance of a 5400rpm laptop hard disk. This system is crying out for a solid-state drive and nor will seasoned tablet users appreciate the long loading times. A version is available with an 8GB solid-state cache, but our review sample lacked this potential speed-boosting features. See: more reviews of all-in-one PCs.