Microsoft has issued a set of guidelines for hardware certification on Windows 8 tablets--a policy it applies to all new operating systems.
While there aren't a lot of surprises (see charts below), Microsoft does specifically address a "convertible" design, which is expected to become popular on both Intel- and ARM-based devices.
Convertible: "A convertible form factor is defined as a standalone device that combines the PC, display and rechargeable power source with a mechanically attached keyboard and pointing device in a single chassis. A convertible can be transformed into a tablet where the attached input devices are hidden or removed leaving the display as the only input mechanism," according to the Microsoft documentation on pg. 87.
Hardware buttons: Must have five hardware buttons. They are--power, rotation lock, Windows Key, volume up, volume down.
Broadband: And many of those designs will have built-in broadband. "If a mobile broadband device is integrated into a tablet or convertible system, then an assisted GPS radio is required," Microsoft stipulates.
Display: will have to be at least 1366x768 resolution. "The minimum native resolution/color depth is 1366x768 at a depth of 32bits. The physical dimensions of the display panel must match the aspect ratio the native resolution. The native resolution of the panel can be greater than 1366 (horizontally) and 768 (vertically)."
NFC: A visual mark is required for near field communications. "To help users locate and use the proximity technology, the use of a visual mark is required," according to Microsoft.
Alternative to Ctrl-Alt-Delete: The new option is to press Windows Key + Power. "For Windows 8, the SAS (Secure Attention Sequence) signal will be sent when the combination of the Windows Key button and the Power Button is pressed."
Other Windows 8 tablet/convertible minimum hardware guidelines include:
- Storage: At least 10gb free space "after the out-of-box experience completes"
- Graphics: Direct3D 10 device w/ WDDM 1.2 driver
- Display resolution: 1366x768
- Camera: 720p
- Accelerometer et al: plus magnetometer and gyroscope
- USB: USB 2.0
- Networking: WLAN and Bluetooth 4.0 + LE (low energy)
- System firmware: UEFI (see )
See complete Microsoft document here (PDF). Note that document has a publication date of December 2011.
Updated at 11:20 p.m. PST: adding bullet item for alternative to Ctrl-Alt-Delete.
Updated at 11:45 a.m. PST on January 18: adding clarification that the Microsoft document specifies guidelines not requirements.