Connecting a graphics card with a TFT flat screen for the first time, an adjustment tool from the monitor manufacturer should be used, otherwise the monitor will flicker. For example the adjustement tool with the ELSA ECOMO 117 LCD is called 'Testptn.exe'.
Sometimes the same steps must been repeated because of the dejustage of the dot clock. Just follow the steps in the setup manual as you did at the first time, you installed the display. A manual justage is not fine enough to fix the dot clock.