How does my family computer have a following situation matter

My family computer has sometimes the following situation the unknown cause will halt or the blue screen after the hot start the black screen and how the display monitor not video signal or period of time starting a good this matter?
With my computer before is the same, should be obviously the card question, I traded the card to be obviously good Around me has a such loom, its reason was obviously the card ventilator has gone bad, after time length, obviously card overheated, after restarting, the monitor did not have the signal, are you had a look at you are also this Tears off in certificate of deposit inserts, the computer after using period of time needs to tear off in certificate of deposit inserts again, will otherwise appear machine, after or the starting, demonstration will not have the signal