How to Fix Red Lines and Dots in Black Areas of a Screen

I was having major problems with red noise on my screen, it appeared in the form of red dots and lines. It happened soon after I updated my NVIDIA drivers, though this fact was mere coincidence. The problem presented itself sporadically, seemingly at random, though it was concentrated in particular on the right side of the screen. I rolled back my drivers from the Beta that I was testing, this did nothing to solve the problem and I noticed that on restart, the problem occured even as the BIOS was loading. I felt that the prospects were nothing if not bleak.

I began troubleshooting. I concluded that there were two likely culprits, either the screen, a cheap 19-inch Corega or the video card, an expensive Asus 8800 GTX. I doubted that the card would be a problem, being that it is relatively new and Asus do some great quality control. The Corega 19-inch monitor, however, has some miles on the clock and is on more often than not. After rolling back the drivers and running some diagnostics on the 8800 GTX I determined that it was not likely to be the culprit. To make matters even more baffling, the monitor seemed to be fine as well. When disconnected from the computer, I could go through setup functions without so much as a sniff of the red dots and lines that had plagued me in Vista SP1.

I could not rule out the video card 100%, but I was hoping that it would be something else. With expectations of the worse, I hit Google and started hunting for solutions. It wasn't long before I found one on a site called Lyalin Blog. The suggestion was to replace the DVI cable or change it to an RGB. I have an RGB cable, but as you know, 8800 GTXs offer dual DVI and no RGB, so that was out of the question. Also, cables are expensive and don't really go bad unless something happens to them. Sitting behind my desk it was unlikely that anything had damaged the cable. I had already played around with the connection in the back of my desktop and the monitor connection seemed very secure. All the same, I loosened the screws, which were strangely much tighter than I had set them. Once I had done this, red noise disappeared completely and the monitor even seemed a little more responsive.

While I am not one to go and take drastic action until a proper troubleshooting session has been completed, some people do. Just make a point of checking your connections before you go buying new cables or, gasp, a new video card or monitor as some people might.

Source: Lyalin Blog