New xps 15 and dgpu info

@Aratheba  Forgot to add this to my original reply.  I created this thread asking about the dGPU wiring of the XPS 15 9500 a while ago and got some answers, which led to a bit of a discussion in case you find it useful/interesting.

Thanks for your answer first of all.

These are very interesting info. Of course I do know that the "basic" xps15 config has no discrete cpu, but it does have a smaller battery too.

I want to use the xps 15 for coding on Linux and thus 99% of the times I don’t need a descrete gpu at all.

As I don’t know whether I’m able to select via software the default gpu to use on Linux I was hoping to be able to disable the discrete gpu via bios. 
The question about which gpu wired the usbc video output is because I don’t want it to consume too much battery just because I hook an external monitor (as mbp16 does).

Nice to read about the xps17, do you know if it gives me the possibility to disable completely the discrete gpu or not?

Thanks in advance

@Aratheba  The 15-16" MBP models have their external display outputs wired to the dGPU, and therefore when you connect an external display the dGPU has to be activated, even if nothing graphics-intensive is going on.  That's why the battery drain increases.  But by the same token, the fact that you do NOT see significant battery drain UNTIL you do that means that the dGPU is able to be kept disabled even without the user having to manually disable something at a firmware level.  The same goes at least on the Windows side.  If it didn't work that way, then there would be no point wiring the outputs to the Intel GPU in the first place, because doing that actually sacrifices some features as I explained in that thread I linked.  I don't work with Linux, so I don't know how it works there, but I believe that it has the same support for NVIDIA Optimus in order to manage this that Windows does, since Optimus has been around for quite a while now.

But you wouldn't be able to select a "default GPU" in software anyway.  In systems where the display outputs are physically wired in hardware to the Intel GPU, then that GPU has to remain active.  I suppose you might be able to set something to force the NVIDIA GPU to be active at all times for rendering, but that's the opposite of what you'd want.  So I would expect that the default setup will already do exactly what you want.  But again, you could just do a bit of research on Linux with previous XPS 15s, since the XPS 15 has been set up with the Intel GPU controlling all outputs at least going back to the 9530 generation that was released in 2013.

As far as I know, the XPS 17 only allows you to choose which GPU control the display outputs and doesn't allow you to completely disable the dGPU.  But again, that shouldn't be necessary in the first place.

I use a xps 9500 and it's performance running a 4k display on the Igpu is lackuster (i.e. moving windows around, windows animations, etc show stutters). How can I make the discrite graphics card drive windows ?.
This is possible in linux