I was using Firefox when I copied the info after a recent crash. The pc is quiet now so I wont be able to try unplugging the back fan at the moment- I will try when it is being noisy. After a few minutes the fan was going normally and the noises settled down. The noise was coming in spurts, like a revving engine and each time there was a 'rev' the fan at the back would try to go. It seems to be coming from the fan area (heatsink?) that is on the motherboard. Last night the noises were loud and the internet crashed numerous times so I took a look inside the pc to see where exactly the noise was coming from. I have done the basic things like running scans for virus's and adware which have not found any issues. I have to keep trying, refreshing, leaving it for awhile etc and then it starts to work fine until it eventually (maybe hours later) begins to crash randomly When I turn it on in the AM, I can not get to any websites or bring in my emails, though I do have a working internet connection. I could not close any tabs individually so just exited the whole lot.

Last night I opened a new tab and it just came up as a blank black page. It has been making some very odd, often loud noises intermittently

I do have the dxdiag if you need more info than I have put up there. Just better let you know ahead of time that layman's terms will have to be used, I am not knowledgeable with the tech stuff. Apologies for the delay (had to feed the horse).

Speccy power supply 12v