Imagine I have a dual agp motherboard with one slot an nvidia card and on the other an ati one (which means no crossfire or sli) (the brands are just for example, but different so that they do not share the same driver), each connected to its own monitor. Then, if I create a full screen window on both monitors with associated DC/rendering contexts.
1/ Will one rendering context report via glgetstring an nvidia driver and the other an ati driver?
2/ If I create only one non full screen window and it spans both monitor, which driver will it refer to? And will it be accelerated?
3/ What particularly happens if I create a window on the ati monitor and move it to the nvidia one?
I tested such setups about 10 years ago, on Windows98, so that may or may not have changed.
I recall that the outcome was getting the correct hardware accelerated GL on primary monitor, and software GL on the second. And when a window spanned both, the primary part looked ok, and the second looked black. Same thing when moving fron one screen to another.
On the fullscreen topic, not really sure but fullscreen will probably not span both monitors.