I recently had a problem on my Dell with XP where the OS apparently went bad. When I could no longer get into Safe Mode, I reinstalled XP from scratch and did all the updates. I also did full virus scans and registry checks to make sure things were okay. Everything points to a problem with the OS being corrupted and not any virus.
Now, at seemingly random moments, a small bar code looking frame will flash on and off in the middle of my computer screen. The rest of the picture is the same - it is just the bar code looking thingy in the center. It only lasts a frame or so, so it is hard to notice unless you are looking right at the center of the screen when it happens. Nothing else seems to happen, but it does it at least every hour or so that I notice.
Seems I have heard of this happening before to someone, but I can’t find anything on it.
Laptop pr desktop? If the latter, ot could be something to do with the on screen display (that you normally only see when you press one of the buttons to adjust something.
Other than that, it could be a problem with the driver for the graphics card, which a simple update may remedy.
Or it could be a problem with the graphics card itself (or I suppose the memory it uses, which is not always intrinsic to the graphics card)
I recommend running the Dell Diagnostics tests on the system. The bar code thing you’re describing could be caused by a defective video card, and the problems you had with the OS might be due to a hard drive that’s failing. The diagnostics should be on one of the CDs that came with the system. If not, hit F12 when the Dell logo appears as the system is booting and the diagnostics may be one of the listed options.