+1. Dead pixel on your screen. Not much can be done. Cheap LED's usually come with 1 or 2 right out of the box. More expensive ones try to weed them out, and sell the screens with dead pixels to companies that use them in the cheap screens.
Good program to use:
1) You can select which color to display (full screen) or auto rotate thru to find bad pixels.
2) You can use the pixel fix, which places a small square that you can move around. You place the small square over the "stuck" pixel and try to repair it. The square size is adjustable. If I remember correct default is a 5 x 5 pixel square.
Bought a new monitor and used it to see if I had a any bad pixels, did not have.