Well, if components on a motherboard are faulty or aren't designed to last (this is especially an issue with people who like to put their laptops on their bed and its underside ventilation is muffled up by blankets and stuff starts overheating on the motherboard and after a while, it just dies...) or are abused, then all it takes is one little issue to bring it all down.
While certain components on a motherboard are replaceable/fixable, you'd need someone experienced and you'd pay. Best thing is to send it in under warranty and have them fix it for free.
If you quietly and knowingly put your laptop on your bed and the poor thing has been suffocating all this time, then don't do that anymore you evil woman!
