Question No display from GPU has power

[Daniboiii]

I have an AMD Sapphire RX470+ OC 8GB,
600 Watt Power supply, had a few issues along the way with it as when I started the PC with my monitor sometimes the GPU hasn't showed any signal to it, and only after starting the PC and restarting it I would have gotten a signal.

Now I've changed my monitor and my GPU doesn't load up at all and I've updated my windows to the lastest version with all of the quality and main updates, Tried to update my drivers for the GPU and it says that there is no card connect or anything.

Tried a few things and can't seem to get any luck.

 

[rgd1101]

make and model of the psu?

 

[Daniboiii]

Seasonic SS600ET Active PFC F3

Thats the full name

 

[Daniboiii]

So I tried a few things and I found out this
My Mobo port does show a signal to the monitor, my GPU doesn't load up and it uses the Intel Onboard graphics and doesn't use the AMD,
The card is running on full power and doesn't send out a signal. If anyone knows anything would really help.

 

[rgd1101]

full system spec?

 

[Daniboiii]

PSU - Seasonic Ss600ET
Mobo - GA-H77-DS3H
Ram - 8 GB
GPU - Sapphire Radeon RX470 8GB OC+
CPU - Intel i7 3k Series