I will wait for your reply, but I want you to check to see what the monitor is connected to while you are inside the computer.
If there is a vertical board that it is connected to which is in a slot, this would mean you have what is called an add-on video card.
The video card makes a connection to the motherboard through contacts on the boards edge and is wedged into a slot where those contacts make contact with other contacts. I know sounds like I am repeating myself huh?
The problem with this type of connection is the two contacts are made of different metals, usually copper and tin alloys.
The Earth's atmosphere has moisture and a large degree of contaminates that float through the air.
These two get together and create a corrosive chemical that corrodes metals.
A great example for discussion is the 1 cent coin, which is made of copper, zinc and nickel alloys.
The coin starts off as a shiny golden color, but over time oxidation and corrosives in the air discolor the coin to appear dark and dull looking.
This layer that builds up is non-conductive, it acts like an insulator and builds up what is called resistance.
In electrical circuits, this same layer builds up where two metals are wedged together, over time, the current passing from one metal to the other is reduced when oxidation takes place, the layer acts like an insulator and creates resistance that increases as time passes.
In the beginning, this may create random issues that come and go, but eventually, as this resistance increases, the circuit involved becomes more problematic to the point it fails to work at all.
If you have an add-on video card, I want to warn you not to ever touch the gold colored contacts on the boards edge that goes into the slot.
The oils on your fingers contain acids that can eventually eat away at those contacts and cause issues down the line.
I suggest if you have an add-on card, safely and carefully remove the card from its slot, and re-install it again.
Reboot the computer, you may find your video problem has gone away because the obstruction was removed.
Another warning you must follow, any time you intend on touching anything inside your computer, you must first take precautions against static electricity and the damage it can cause to the motherboard.
Touch the metal computer case before touching anything inside the computer case and make sure your computer is not connected to the AC power outlet.
Edited by MrBruce1959, 18 February 2011 - 01:58 PM.