DPT was written to help me check my own screens (Couldn't find one that worked across multiple desktops so had to write my own!) by cycling through the three primary colours used (red,green,blue) and all on (white) and all off (black). Simply select a colour then closely inspect your monitor in each of the primary colours checking for pixels that are not operating as expected. Stuck pixels (always on) are easier to noticed then pixels that are not on due to their size (normally under .5mm).
In most cases, a stuck or dead pixel is impossible to fix (some people rub them gently with a cloth etc. search the net for other ways), however most manufacturers have a policy which will specify that after X amount of dead/stuck pixels they will replace the screen free of charge (in warranty period). You can use DPT to help identify IF you have any pixels and how many in order to see if you qualify for a replacement screen/laptop... no guarantees though!
In most cases, a stuck or dead pixel is impossible to fix (some people rub them gently with a cloth etc. search the net for other ways), however most manufacturers have a policy which will specify that after X amount of dead/stuck pixels they will replace the screen free of charge (in warranty period). You can use DPT to help identify IF you have any pixels and how many in order to see if you qualify for a replacement screen/laptop... no guarantees though!