Razer Blade 13 2019 Late external monitor only using IGPU

Just bought Samsung 49 CRG9 and using USB-C to HDMI cable.
The problem is when I plug a cable into the laptop it will only use IGPU, not DGPU.

I have uninstalled and reinstalled all software and drives and windows running the latest OS.

Monitor works fine on other devices and the cable also so I've been able to isolate it to the laptop.

Any ideas why it's going this?

I have attached photos and refs