1. If your monitor is only blurry in some games / application its most likely due to specific settings or hardware limitations.
2. Windows Vista requires 256 MB of Graphics memory.
Use a 256 MB Dedicated Graphics Card or when using Intergraded Shared Graphics Memory make sure there is 256 MB of free RAM available. (Check via CTRL + ALT + DEL > Task Manager > Performance)
3. Remove and plug in the power and display cable. Remove and fix the graphics card on mother board.
4. Install latest Version of Direct X. ( http://www.microsoft.com/downloads/details.aspx?FamilyId=2DA43D38-DB71-4C1B-BC6A-9B6652CD92A3&displaylang=en )
5. Install / Upgrade to latest graphics display drivers. (Check Device Manager > Display - Make sure it matches with the graphics card you are using)
Right click Computer > Properties > Device Manager
6. Install / Upgrade to latest monitor drivers. (Again check Device Manager > Monitor)
7. Reset the monitor to default settings. ( Auto / Reset button on Monitor)
8. Change the display to native resolution. (Resolution recommend on product features)
Right click on Desktop > Personalize > Display Settings
9. Change Colors to Highest (32 bit) in Display Settings.
10. Change the screen refresh rate to 60 Hertz.
Right click on Desktop > Personalize > Display Settings > Advance Settings > Monitor
11. Enable or Disable Clear Type / Standard.
Right click on Desktop > Personalize > Windows Color and Appearance > Effects > Use the following method to smooth edge of screen fonts
12. Let Windows Choose.
Right click Computer > Properties > Advanced System Settings > Advanced > Under Performance Settings > Let Windows choose what's best for my computer
13. Try it on another computer.
If it still doses not show clear display your monitor is very likely to be defective or has got damaged.