If you have connected your TFT via an analog VGA cable, you might have some blurry vision or even flickering in some cases. If the following picture shows some flickering or looks blurry, your display needs calibration.
To calibrate your display, go to Randy Simons' page and do the following:
- open the sync pattern page
- put your browser in full-screen mode (mostly by pressing F11)
- issue the auto-calibration on your TFT display (most displays have a specific "Auto" button)
- make sure the picture doesn't flicker anymore
- exit full-screen mode (F11 again)