hdmi extension cable to connect an extension cord affect signal

Connect the extension cord will certainly be some hdmi extension cable. Connection, the gauge to see if the line is not so good. Not long natural. Plus connector is generally not recommended
Underground with no impact on the wall, of  WISDOM sfp module course, it also depends on the materials used to the line. If the material is not good, it is natural hdmi extension cable affected. General standard materials are no problem.
If you want to embedding, recommended not to buy the materials used bad line. The long-term will require 24AWG. 1, DVI, and HDMI is a digital interface, HDMI but also in addition to the video with audio, typically used to connect DVD player, etc., while the video and audio output devices, it is also called a multimedia interface, a single DVI digital video interface, generally used to access the LCD monitor.
2, the computer connected to a TV, the two WISDOM rca audio cable  interfaces are inappropriate, the adapter module requires a dedicated, high cost, there are losses, the effect is not necessarily directly with both the TV and the video card has a VGA good.
3, VGA is an analog video interface, can be connected directly, just use a good quality cable signal loss actually feel it, pay attention to the audio to separate pull, TV VGA input port side of a dedicated 3.5 audio input jack.
4, to make television sets and monitors simultaneously with, you can buy one for two VGA connector (note pin hole to correspond), click on  WISDOM dvi adapter the video card installed inside the 2nd monitor and check the "extended to the desktop", so You can point your browser to live, the right player to pull on a TV monitor, the computer is not wrong doing other activities.