Originally Posted by
Raivyn
it's possible that your monitor clarity etc, or the distance you are from your monitor, or the lighting of the room is having an effect on this. Typically you don't want to stare at a bright monitor in a dark or dim room, this can cause problems. Also you don't want to be too close to the monitor. In addition, the clarity of the monitor may be causing your eyes to strain to see the image.
It is also possible that your computer chair is fucking up your spine and giving you tension headaches - where are your headaches located typically?