If there is a problem, contact your vendor immediately. A mainstream manufacturer will have a customer support system you can contact. A problem to watch out for with LCDs is dead pixels. After you hook your monitor up, run a totally white screen and look for stray black dots then switch to a black screen and check for white or coloured dots. You'll be able to live with a few dead pixels but you don't want to have a cluster in the middle of your screen.
Warranties differ on how many dead pixels constitute a defective screen.
One of the best ways to evaluate a monitor is to run diagnostic software like DisplayMate . You can download free demo versions of some programs or test your monitor online. The software is designed to help you optimize contrast, brightness and image size. It provides test patterns like those you see on TV that test focus, colour and geometry. The monitor controls should be able to correct noticeable distortions, if not there might be a defect in the monitor or the controls.