My computer, running Windows 2000, was having garbled display. First the mouse droppings which the refresh wasn't eliminating. Then slowly more and more disturbing visual elements started covering the screen - lots of lines and dots and colors. It is as-if someone decided to add tons of noise to my screen.

It progressively and rapidly worsened till it was impossible to view anything on screen. The problem started to manifest even while booting.

What could potentially be wrong? Was it Software Virus, Graphics Card, Driver or Monitor? Lets step through the possibilities to a startling solution.

First I checked the monitor. A different monitor displayed the same problem. Monitor was not the issue.

Then I tried to view the screen using VNC (Popular free remote screen capturing utility). It looked perfect.

I use AVG (Popular free anti virus software), which is updated with new virus definitions every night, along with Zone Alarm (Popular free firewall software).

Due to three factors stated above I could safely rule out virus infection. Also I haven't heard about any new virulent boot-sector virus these days. They are rather easy to detect, even new ones, with heuristic scanning.

Obviously by this time I had gone through Microsoft troubleshooting help, which as always was totally useless drivel. And then it gives up very easily.

I thought the graphics card was the most likely problem at this point. I have integrated graphics card on a Intel chipset Motherboard.

One of my other machine was having problems too. On powering it was giving strong burning smell. On investigation we found one of the 256 MB DDRAM memory was actually burning! So I replaced it with a 256 MB DDRAM Hynix memory from my first machine.

Now something funny happened. I saw the same garbled display on this machine too. It was the memory all along!

The video card was using portion of the RAM for its display. A bad memory gave it all the troubles. All I had to do was remove the defective memory and my machine was up and running, albeit with lower memory.

I had seen defective computer memory contributing to lots of problems but never a garbled display.

Lesson learnt: Almost always first eliminate (computer) memory as a potential cause of problem.

Update: Interestingly the same defective RAM works fine on Windows XP machines and is currently being used without any problems.