Question Newly built pc wont display on tv

[Jospeh3847]

so I've just built a gaming pc for the first time and the pc turns on and all the fans and lights start working so I assume everything is working so I have connected the hdmi from the gpu to my Samsung TV and I get no signal.
Also the pc doesn't allow me to turn it off (I have to do it from the psu) can someone help me.

Do i have to have a monitor to do the boot up and post the motherboard I use is b450m ds3h also there is a yellow light on the motherboard not sure if that indicates anything

 

[rgd1101]

full system spec? include make and model of the psu

 

[Jospeh3847]

full system spec? include make and model of the psu

Evga 450br power supply
B450m ds3h motherboard
Geoforce gtx 1660 super
Ryzen 5 2600 cpu
Corsair 2x8gb vengeance

 

[Cesar V]

Evga 450br power supply
B450m ds3h motherboard
Geoforce gtx 1660 super
Ryzen 5 2600 cpu
Corsair 2x8gb vengeance

I got the same problem with everything component the same except the gpu and a Corsair 450 waty