|I assume it just suddenly started doing this and was not related to anything you did at the time.|
Not hopeful but better try the motherboard discharge routine:
Turn off laptop, remove power, remove battery, hold Power Off/On button down for at least 20 seconds before re-assembly.
Have you had a good look for dust build up, particularly CPU heat sink, fans and vents?
Might be an idea to clean the RAM edge connectors with a pencil eraser while you are in there. Also check all connectors for tightness.
Always pop back and let us know the outcome - thanks
message edited by Derek