VGA over CAT5e

The setup

Originally I had run 3 pairs of standard UTP CAT5e in the wall from the monitor's location to a closet where the PC is located (about 35' per run). Each CAT5e was then terminated with standard 110 style keystone jacks (color coded on both ends; blue for VGA, black for USB, etc.). From there, custom cables were assembled for both ends for USB, audio and VGA.

The custom VGA cables were terminated with standard RJ-45 plugs on one end and HD15 male solder connectors with metal hoods on the other end. Snap-on ferrites were added on both ends for good measure.

Using one pair of CAT5e connected to pins 1,2,3,6,7,8,13, and 14 I was able to get quality 1680 x 1050 video with minimal ghosting/ringing.

As a side note, the USB works fine for a keyboard, mouse and remote as long as you have a powered USB hub at both ends. Also, the audio works fine with no noise while the system is powered on. When off, there is a 60 Hz hum from the line voltage wiring that runs nearby. This is easily rectified by turning off the speaker system when the computer is off.

The problem

After switching my home DVR system over from Windows Vista Home Premium to Windows 7 Ultimate the LCD monitor that was remotely connected via a single pair of CAT5e no longer would work at its native resolution of 1680 x 1050. Obviously, Windows 7 didn't like that it couldn't get monitor information over the cable.

The solution

Quite simple actually... Connect the remaining seven HD15 pins using a second pair of CAT5e and move the USB and audio on the same CAT5e run... Success!

Below are the pinouts I used:

Elsewhere you may read about impedance matching the cable (VGA coax has 75 ohms resistance while UTP CAT5e has 100 ohms) by attaching a 24 ohm resistor in series on each of the three video signal wires (red, green & blue) on both ends (6 resistors total). I did this, but did not notice any improvement on the minimal ghosting/ringing that I have. I did however get reduced contrast; which was expected. YMMV.

Good luck!