Here is an interesting online tool where you can check and cure dead pixels of your LCD screen, fix brightness, gamma, phasing, flicker, etc of your computer monitor. For instance, if you're thinking of buying a new monitor then try to get one without TN technology or if you're not sure if your monitor is TN run the TN checker.

TN Technology means color is not consistent and depends on where you're sitting. If block color seems to fade when viewing the TN checker page it may mean you have a low budget TN powered monitor.