Hardware certification requirements for  Windows tabletsGraphics
CardDirectX - 10 graphics device with WDDM 1.2 or higher driver
Storage -10GB free space, after the out-of-box experience completes
Standard buttons -'Power', 'Rotation lock', 'Windows Key', 'Volume-up', 'Volume-down'
Screen - Touch Screen supporting a minimum of 5-point digitizers and resolution of at least 1366x768. The physical dimensions of the display panel must match the aspect ratio of the native resolution. The native resolution of the panel can be greater than 1366 (horizontally) and 768 (vertically). Minimum native color depth is 32-bits.
Camera - Minimum 720p 
Ambient light sensor - 1–30k lux capable with dynamic range of 5–60k 
Accelerometer - tg3 axes with data rates at or above 50 Hz
USB 2.0 -At least one controller and exposed port.
Connect - WI-FI and Bluetooth 4.0 + LE
Other     -  Speaker, microphone, magnetometer and gyroscope.      If a mobile broadband device is integrated into a tablet or       convertible system, then an assisted GPS radio is required. Devices supporting near field communication need to have visual marks to help users locate and use the proximity technology. The new button  combination for Ctrl + Alt + Del is Windows Key + Power.