Today my system started behaving strangely. While surfing the web the monitor started displaying gibberish, then the display turned to black for a few seconds, then turned back on and was displaying other gibberish, then turned to black again. The monitor power led was blinking which meant it wasn't receiving any input.
I then rebooted the system via case button. During the POST, everything was displaying normally except for the fact that each displayed POST sequence had either green lines or blocks on the black background, underneath the text, and this changed with every sequence. On a later restart, I noticed that these artifacts are exactly the same, they don't change.
Once Windows 7 loaded up, everything displayed as if the display driver was disabled, and there were thin semi-transparent light opal horizontal lines in rows on top of what was displayed, only that they weren't over the whole monitor, they seemed to make two curbed patterns of concentric quarter-ovals, with the ovals' center in the bottom right corner, and there were patches on the display where the lines didn't show.
In any case, the exact description might be unimportant. I checked the display card in "device manager" and noticed the icon had the yellow warning triangle that meant an error, and accessing its properties it said that "Windows has stopped this device because it has reported problems. (Code 43)". I tried uninstalling and reinstalling the driver, changing the monitor to the second display port and connecting a different monitor but it didn't change anything. I opened up the case, took out the card and blew all of the dust out of it, but again nothing changed.
I took a screenshot of the display, saved it and sent it to another system I have, and the image displayed correctly, without the added lines. Additionally, I noticed that when moving a window over the desktop the lines themselves displayed over everything without changing their position, though they actually show according to how dark the color beneath is. This is best noticed when opening a picture, and even more so in paint, where filling the coloring space up with different colors showed that the lines appear on certain colors and not on others.
My question is, what could have happened? What could be wrong? What malfunction would make the card still display an image yet behave like this? Any opinions or suggestions are highly appreciated.
I use an nVidia 9800GTX+ in homebuilt system that's about 2 and a half years old.
I just remembered that I had another issue with the system about two months ago that also seemed to be graphics card based. The monitor didn't display anything even though the card was receiving power and the fan was spinning. Since all components are still in warranty, I took it to the distributor where I bought everything, and after trying multiple things the clerk who also serves as IT support tried resetting the motherboard BIOS which solved the problem. Could the current issue also be BIOS based?