Razer Viper Vs. ASUS GX850
The Viper by Razer uses an Optical sensor from Razer, specifically the 5G, providing a DPI/CPI range of Up to 16,000 DPI. This results in a tracking speed of Up to 450 ips, and a maximum acceleration of 50 G. with a 2.1 m cable. The Viper is considered to be an ambidextrous mouse. It weighs in at 69 g without the cable and is approximately 126.7 x 66.2 x 37.8 mm (LxWxH).
The GX850 by ASUS uses a Laser sensor from Avago, specifically the A9500, providing a DPI/CPI range of 1250, 2000, 3500, 4500, 5000dpi. It uses a USB connection. It weighs in at 150 g grams with the cable and is approximately 124 x 72 x 42 mm (LxWxH).