When i turn on my laptop all i get is a black screen

Possible that PC is hanging up as there is fault on the OS (operating system) or a virus in the OS. Also it is possible that the backup battery (CMOS) has low voltage or the memory card is a suspect. In this case you need to check the voltage and also try and swap a memory card. Sometimes the memory card connections can be faulty either on the card or on the slot. Cleaning the slot and card must be done before you try a replacement. If the PC boots and fails then the hard disc can have bad sectors or is corrupt. However if there is no result the motherboard also can be suspected. In this case you might need the help of proper tools and equipment support to do a chip level service