Dell Inspiron 3650 i3-6100 Graphics Card Upgrade

My monitor supports 1920x1200 resolution, but the most I can get out of the onboard Intel HD 530 is 1920x1080. I have tried adding a custom resolution of 1920x1200, but it says the system does not have enough bandwidth for this resolution.

I fitted an Radeon HD 5450 to the machine, but I can not access the BIOS with this fitted. The machine does successfully boot into Windows 10, but I can't access the BIOS at all. I believe this is because I have "UEFI SECURE" more enabled.

If I turn off SECURE mode, then it will work ok, but I want to keep SECURE mode on.

I am limited on power, as the Dell Inspiron 3650 only has a 240W supply.

I have seen suggestions of the GEForce GT730. Does anyone have one of these and can they confirm they boot ok with SECURE mode on?

Alternatively what other graphics cards are people using with the Dell Inspiron 3650?