AMD Ryzen 7 3800x, ASUS ROG STRIX B450-F, GTX 960, Corsair vengeance RAM 8gb. When started the CPU fan does not spin and the QLED trouble shooting light goes orange/red (Red indicates CPU issue). The fan runs if the CPU power cable is disconnected but stops once it's connected, however. There's also no beep or POST; the monitor remains completely black. Furthermore, the PC won't turn off via the conventional case button and has to be turned off at the mains each time. The case and GPU fans spin and the motherboard RGB LED's light up signifying it has power, and the PSU is 450watts, so is unlikely to be the issue. I tried another CPU and the issue remained. Ran the system without the GPU installed and the issue remained. Used different RAM alongside placing it in different slots, yet the issue remained. CMOS was cleared yet the issue, once again, remained. Every cable is in correctly (as far as I'm aware, pictures can be provided). The only problem I can now think of is a defect or incompatible motherboard, yet ASUS's website says that the CPU is compatible. I'm not sure how to check if the motherboard is defect/damaged. Evidence points towards an issue between the motherboard and CPU however am not one hundred percent sure. Help would be very heavily appreciated as I'm building this PC for a friend and they need it ASAP.