Why does my screen get black/shadowed

dancer25

Honorable
Dec 16, 2012
2
0
10,510
Hello,
My Dell inspiron often shadowes my screen. What i mean is, that i can work on it, or play, or watch a video, and out of nowhere, the screen will turn black, but if i move to the sides, i can see some parts of the screen, like it is being shadowed. Sometimes it lasts a couple of seconds, sometimes it doesn't come back for hours. It is really disturbing and i wonder what causes this.
Thanks!