Blury display Windows 7

Hello,

today I have encountered a strange problem. Once I turned on my PC I have noticed that most of my screen looks a bit blury. Especialy the fonts. The issue has not been observed before. I did not install anything that could affect the screen the day before.

My Video card is: ATI Radeon 6900 HD
Screen resolution: 1920x1080
Windows 7 Pro

Untill now I have:
1) Updated CCC, Video Drivers, All updates in Windows
2) Uninstalled the drivers, and installed the old and new video drivers
3) Tried swiching on/off morphological filtering
4) Adjusting ClearType fonts
5) Removed the graphics card, and cleared all the swiches, and cables.

Can you suggest any more solutions to my problem?