Pm Nic mate. My computer at home recently did this and it didn't end well unfortunately...
Mat try unplugging anything usb like keyboard , mouse etc and see what happens. Pretty much just leave the monitor and power plugged in.
Then boot it .
Sent from my SM-G920I using Tapatalk
Cpu will shut down after certain temp threshold is reached but it takes a fair bit to cook it completely , so i doubt it's cpu ...
The fact it's gradually got worse throughout yesterday could be a psu filling out retirement papers.
It's very hard diagnosing remotely .
Honestly could be a number of things given symptoms so far.
Sent from my SM-G920I using Tapatalk
I just had exactly same issue, lights, fan, power buttons all working but no video out and it wouldn't post (no beeps or error codes on board). It was the CPU
….................... On the move
good to hear mate. @nissannewby got his gear from the same place as you so he should be all covered =D