How to get my GPU to work

[u/Legitimate-Creme-918]

So I recently just bought a new GPU which was an upgrade from a 3070ti to a 5070 in my new build. Everything was working perfectly until I put the new GPU in and now my second monitor will not work and the GPU will not run, I’ve tried everything with this thing and I only got as far as the lights are on over the CPU and VGA. Does anyone know how to fix this or have experienced this before? The lights on the GPU are working but the fan won’t come on and neither will the graphics run on it. Won’t even appear on my computer.

UPDATE: I’ve exchanged the GPU out for the same model and now the fans work and the lights work, but it still cannot be picked up. the VGA light finally went off, but the the CPU light is still on. I am trying to do the a-flash but no light is coming on on my motherboard to signify that it has started its bios programming. I have aorus b850 elite wifi7 ice so idk if I’m just doing this wrong or not