[Sultan]

http://en.wikipedia.org/wiki/Digital_Visual_Interface

The maximum length of DVI cables is not included in the specification since it is dependent on bandwidth requirements (the resolution of the image being transmitted). In general, cable lengths up to 4.5 m (15 ft) will work for displays at resolutions of 1920 x 1200. Cable lengths up to 15 m (50 ft) can be used with displays at resolutions up to 1280 x 1024. For longer distances, the use of a DVI booster is recommended to mitigate signal degradation. DVI boosters may or may not use an external power supply.