Laptop help needed. Black screen and loud noise?

Every now and then my laptop decides to black screen and make this loud noise. It is a Lenovo Z500 that I've had for a couple of years. Now about a couple of months ago my laptop fan started clicking and before this I had no issues like this (just in case it's connected.) I have to hold the power button to turn it offT and the laptop turns on again after some time. I read somewhere online that it could be the heat sync or a cooling issue? Many thanks

Read more: Laptop help needed. Black screen and loud noise?