There is a severe issue with ALL Source engine games (Counter-Strike: Global Offensive, Dota 2, Team Fortress 2 etc.) where the Source engine will only detect the Intel integrated GPU even though the game will render with the AMD GPU. This leads to the Source engine locking out dynamic shadows and anti-aliasing options. Let me clarify that this is not an issue with the game using the right GPU to render, it's an issue with the initial detection of the GPU which causes the game to list it's detected GPU as the Intel one, even though you can see that it's rendering with the AMD GPU. Nvidia has already reportedly solved the problem months ago, but AMD users are still stuck with being unable to use these options. Apparently this was an issue with Secure Boot on UEFI PCs for NVIDIA users. However my PC isn't enabled with UEFI/Secure Boot so I'm not sure what the issue is. I've contacted Valve developers about this issue and they've responded with:
"The Secure Boot problem was specific to the NVIDIA driver, IIRC. I would contact AMD for support about this particular issue."
You can see in this image the game detects the Intel GPU even though it's rendering with the AMD GPU. I do not believe that this is a bug that end users can solve, this has to be fixed in a driver patch.