Computer crashes

[scrambler1958]

Hello,
does anyone know why my computer keeps crashing when I play videos? It sometime takes a few minutes but it always eventually crashes.
Can anyone offer any help?

 

[hang-the-9]

Most likely is the video card is overheating. Does this happen with games as well? By games I don't mean simple web games, but real games. How does it crash? Any error messages or does the whole PC just lock up and you need to power it down?