Late yesterday the screen on my laptop started acting up.

The desktop picture was tearing badly and impossible to see the icons, this included items on the task bar. Initially I thought it was related to f.lux which I had recently installed, so I uninstalled that with no improvement. Then I thought perhaps the CPU/GPU was over heating as I had been using it in a location where the vents were partially blocked.

Last night I did some initial testing by plugging in an external screen and the image on that screen was OK. It's a different resolution and when it plugged in the laptop screen resolution also changes. 

Tonight I pulled the laptop apart to check the screen cable and connections and couldn't see anything obvious. I've put it back together in a temporary fashion and booted it back up.

The problem still exists. I've noticed some unusual things. For example opening Opera makes the screen image stable and completely readable with no tearing what so ever. If I open another app, Word, Excel, Outlook, Adobe Reader (it doesn't matter which one) the screen becomes torn again. If I minimise that app the screen becomes readable again providing Opera is maximised to full screen.

The screen accessed from CRTL ALT DEL is always stable with a very small amount of tearing at times.

At times when the screen isn't torn the icons on the desktop have ghost images.

About the only app that gives a stable normal picture is Opera.

Tonight when I tried the external display all the screen tearing problems went away and other than the incorrect resolution for the screen the problem went away.

I've checked for a graphics driver update, but it appears I have the latest driver. I've done a restore but no difference with that either.

It seems to be a software/driver issue but I cannot figure out what.

Any ideas?

Thanks for any help anyone can give.