TV turns on but there is no picture or sound, randomly happend before

The Tv turns on and off but has no picture or sound, was working fine for me before (only had it for 2 days) no warranty or anything though sourced it through facebook.

have got a few pics of the tv opened up, if anyone could Identify what Is wrong that would be very appreciated! also note all the boards are Samsung

I was also using it as a monitor not sure if that has anything to do with it.