How does integrated graphic card affect dedicated gpu card performance?

Question

so if i have integrated gpu turned on with the dedicated it could be some performace loss compared to if i would have running the whole laptop just from the dedicated Nvidia GTX 860?

another question is will Directx12 use IntelHD Graphics with Nividia card simultanously or this is just available for desktop integrated GPUs?

Answer 1

"so if i have integrated gpu turned on with the dedicated it could be some performace loss compared to if i would have running the whole laptop just from the dedicated Nvidia GTX 860?"



Typically under Windows, if you have an integrated and a discrete graphics installed, then while the laptop is running on mains power, then the integrated Intel graphics will be turned off, while the Nvidia graphics does all of the work. If on the other hand you're running on battery power, then the Nvidia graphics gets turned off, and the Intel graphics runs everything.



"another question is will Directx12 use IntelHD Graphics with Nividia card simultanously or this is just available for desktop integrated GPUs?"



Under DirectX 12, there is a feature called Multi-Adapter, which will let you use multiple GPUs on the system simultaneously (so embedded and discrete graphics can both be running at the same time). It's a much more sophisticated system than the existing SLI or Crossfire. It will even allow you to use GPU's from different vendors at the same time, like AMD, Nvidia, and Intel all at the same time. But this feature will likely require specific support from games to work. I wouldn't expect the first generation of DirectX 12 games to have support for this yet.

Answer 2

With Nvidia Prime in Nvidia drivers, I believe that your computer individually runs one or the other of the graphics chips at any given time, not both. That is controlled by GeForce Experience in Windows. Although, in Linux I need to reboot only when switching from Intel to Nvidia (GTX 765M), not when switching Nvidia to Intel (HD 4600).



At first in Linux there was something called bumblebee that required a prefix program to switch hybrid graphics on the fly (optirun or primusrun), but that was slower because it routed the output from the Nvidia chip through the always running Intel chip. But Linux Nvidia drivers include nvidia-prime to discreetly run one or the other, just not on the fly like in Windows (although, Nvidia to Intel can be switched without rebooting).

Answer 3

My biggest beef with integrated graphics is that you end up with a lot of extra heat on the motherboard.



This can be solved with upgraded cooling (and a cooling pad) - but of course, even laptops with discrete video cards usually require extra cooling.