Is it a Desktop or Laptop?

Laptop power cords often will come loose and if the battery is not charged or is not in the machine the computer will turn off.

Laptops are more liable to overheat- but they usually are ok after they cool down.

does it work normally now -other than the date is being messed up?

Sometimes the fan is set to run quietly and then speed up when it needs to and it does make a lot more noise then.