What's the ambient light like around your work area? Try dropping the brightness of the LCD panel some or brightening your surroundings a little, this is usually what folks are sensitive to on LCD screens.
Though, another common source of strain is that with the fixed pixels on an LCD, sometimes, text can be too "sharp" which is unatural and can cause strain. Much like being in a dead silent room hurts the ears, there's a certain level of imperfection that we are adjusted to. A possible solution here is to use a built in feature of Windows called "cleartype" that will soften the appearance of text and make it easier on the eyes.
Finally, looking through some reviews about your monitor it is said to some
ghosting and blurring which would readily cause eyestrain. There's no real remedy for this aside from minimizing the amount of movement on your display and to take more periodic breaks to refocus your eyes on something across the room.