Display screen fades to blue/purple after 5 min of normal viewing

Display screen fades to blue/purple after 5 min of normal viewing, and if I push/pull the display screen as far back as it allows, the screen comes back to normal view only if I hold that screen back really hard in which I cannot type with left hand as I'm having to hold the screen in this position. If I let go, the display screen fades to blue/purple. I notice as this is happening, the corner of where the Logic board is located, becomes very hot. I removed the back of computer off and fan is running, and logic board is very hot just in that corner. Could it be a connection of the Screen to the computer? could it be the heat sink? Can the Power cord cause this problem as well? Help. I replaced the battery and nothing different and someone mentioned the IO, OD, O-something but cannot find anything on this.