The game can only detect display/GPU combinations that are active when it starts. There is an option in the graphics drivers to start specified applications on the discrete graphics, though it doesn't always work.
In the graphics driver settings, make sure the game is set to run on the discrete graphics (right click an open area of the desktop to start the nvidia Control Pannel or AMD Radeon Settings). It varies based on the GPU and driver version, but there should be a section where you can have specified applications start either on the 'high performance' or 'power saving' GPU.
Did you try checking the laptop's power saving option to set the GeForce/Radeon graphics to default globally? Also, check if there are different settings there for power vs battery use. Right click an open area of the desktop, and if there is a 'Graphics Properties...' menu option, you can open Intel's Control Panel (Advanced Mode, 3D tab) to set the laptop to Performance mode, as well.
At least with the original release of D:OS, this issue was sometimes just cosmetic, and switching the game to use integrated graphics in the graphics drivers would drop the performance). That was rarer in the Enhanced Edition.
Check if your laptop has a 'secure boot device' option. Disabling that generally helped with those who encountered this issue in the original release (that is more common in laptops designed for Windows 8). See the old topic Graphics Adapter Not Recognized by D:OS for details.
If that doesn't help, you could try disabling the integrated graphics. Unfortunately, the layout and options in the BIOS vary between different motherboards. It should be listed under 'graphics' or 'system', possibly after enabling an 'advanced mode', or going into an 'advanced settings' section. You should be able to download a BIOS manual from HP's support website. There should be a specific key or key combination to press on startup to get into the BIOS (Esc and F10 are fairly common), which should be shown on screen before Windows starts to load. However, this might just get the game to start on the 'Microsoft Basic Render Driver', rather than the discrete GPU.
