I have a basic question that has come to mind because I'm shopping for a new laptop. I've never had a pc with dual switchable graphics, Intel + dGPU. How does that work wrt to monitor profiles? Take as two examples the 15" rMBP and the MS Surface Book. Does the dGPU always take over with certain apps: PS, C1P, etc? Or do these units switch back and forth based on operations or work load within the apps? Does one have the ability to profile both the integrated and dGPU separately for each display, or have to pick one (dGPU)? I feel like I should know this, but I've never had to consider switchable graphics before.
I've not had the time to exhaustively test this but I've not found information or evidence to dispute it either:
I think the idea of the graphics card affecting the calibration of the display is a hold-over from the world of analog display systems (CRT and analog-driven LCD).
In that "age" the D/A converters in the graphics card, along with the cables and connectors had a particular "signature" that could be unique to the system. Variations between systems could cause one system to behave differently than another (connected to the same physical display). As a result, the prevailing advice was to calibrate each system separately - even if they shared the same display (like two CPUs sharing a display, many CPUs sharing a projector system, etc).
In the digitally-connected world of digital displays, we have not seen evidence that the calibration curves in the graphics card, the cables, or anything else in the display chain is affected by changing any component other than the display itself. In other words, for a single display, one calibration / profile could fit all.
I'm curious if anyone else has seen these results.