Flickering is usualy caused by a refresh rate that is to low or a brightness that is to high.
IF you use Windows:
Right-click the desktop and sellect "Properties"
Sellect the "Parameters" tab.
Click the "Advanced" button.
In the new dialog, sellect the Screen tab. (can be monitor depending on the version or language)
You have a drop down list with a number followed by "hertz"
Put a check in "Hide unsupported modes".
Click Apply.
Chose a higher refresh frequancy.
Click Apply again.
A dialog with a count down will appears. If the display is OK, click the OK button.
If the display goes blank or is unreadable, after a few seconds, the display will revert to it's former setting automaticaly.
Also, reducing the brightness of the monitor can help reduce the perceived flickering.
Electro, July 2011