HP ENVY All-in-One 27-b1XX - Display Adapters

[rstofer]

I have an HP Envy All-In-One and it has two display adapters.  There is an Intel 630 and an NVIDIA GTX 950M.  On the back, it has HDMI In and HDMI Out with a little pushbutton to select between internal and external signals to the screen.  Other than that, it's just an ordinary 27" touch screen display.

Like this but older:
https://www.hp.com/us-en/shop/pdp/hp-envy-all-in-one-27-b235t?cq_cmp=12690829826

The question I have is which video adapter is driving the screen?  It only comes up because I started playing with the NVIDIA CUDA cores and this clearly works.  I was expecting the display to blank during the execution of CUDA kernels but I haven't seen it so far.  Of course, the cores are pretty fast and there's a bunch of them.  In this case bunch = 640.

I have attached a copy of the Display system information.

[coromonadalix]

the intel 630  should be the default one in the system, but when you add the gtx 950 it can become the main video card if you have some settings in the bios like primary / secondary  ...  primary boot video

sometime adding a second extrenal card on the pcie lanes can automatically become the first one / main video card ..