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Test

Please test the power supply, record the findings and then replace the power supply with a test power supply. If the PC turns on, the power supply is faulty and needs to be replaced.
Most likely a motherboard fault as all other peripherals have been checked / disconnected. If the power supply and the motherboard appear to be faulty, there is a good chance that there was damage by a power surge, electrical fault or lightning. Components that need to be replaced:
  1. Motherboard
  2. Memory
  3. CPU
  4. Operating System
According to Microsoft Terms and Conditions, a dramatic change in hardware calls for replacement of the Operating system. You can read more about this at https://www.microsoft.com/en-us/Useterms/Retail/Windows/10/UseTerms_Retail_Windows_10_English.htm  
A Component/Peripheral is causing the PC to not boot. Add the components back to the PC one by one and retry with each addition until you find the faulty component.