dGPU and iGPU clashing with each other when multiple monitors are connected

Rhino does not work properly when I have multiple monitors plugged in. I believe it has something to do with a monitor running through the iGPU and creating confusion for the program to understand (This was the best response I received from my friend who knows more about computer engineering than me).

I have an Acer Predator 15 laptop.

  • Intel® Core™ i7-6700HQ CPU @ 2.60GHz
  • nvidia geforce GTX 980m 4gb vRAM
  • 16 gb RAM
  • 64-bit operating system, x64-based processor

I have 3 other monitors (total of 4 including the primary laptop screen) plugged into the laptop.

  • 1080i display connected to the display port
  • 720p display adapted from VGA to HDMI connected to the HDMI port
  • 720p display adapted from VGA to THUNDERBOLT connected to the THUNDERBOLT port

With everything connected and rhino opened on my laptop screen everything appears normal, the problem comes when I try to do anything in the viewports. For example: drawing a line does not show in view unless I click out of view (such as clicking the viewport tab or closing the program and waiting for the “do you want to save before exiting?”) only then does the viewport update and show changes. The same thing goes for rotating in 3D space in the perspective tab.

Only does rhino work once I unplug all my monitors and it runs just like normal. I have tested other modeling programs such as 3ds max with everything plugged in and it runs just fine.

  • However - a similar problem happened when I tried to open a photo in photoshop and photoshop would not produce anything on the canvas. Again, photoshop opens just normal, I can select my tools and click around, but not show in view the image I opened. Only once the monitors were disconnected would it actually begin to work.

BUT I managed to get photoshop to work even with all my monitors connected by unselecting “Use Graphics Processor” (Edit>Preferences>Performance) and everything began to function as normal. But I do believe that photoshop is still actually using my GPU because in task manager it states it using “GPU 1 -3D” which is my dGPU not iGPU engine.

SO i believe that I need to somehow trick rhino into using the correct GPU…

I am not sure if this is the correct place to ask this question but I figured someone might have experienced the same/ similar problem and be able to help me. It’s honestly just an inconvenience to unplug my monitors when I go into Rhino.

You may want to check your NVidia settings according:

Didn’t seem to work. :confused:

Make sure you set the main display to a monitor attached to your Nvidia GPU.

My main display has always been my laptop screen. Only the HDMI port, when another monitor is plugged in, doesn’t affect rhino. But either way, I always have my laptop screen as my primary monitor.

Does running _SystemInfo in Rhino tell you the Nvidia GPU is used? Attach here if you are unsure what the info means.

In both instances, monitors plugged in and unplugged, the information is the same.

The Nvidia GPU?

Yes, it states it’s using it.

Not sure what to suggest next, other than ensuring you have the latest drivers for your GPUs.

Then hope for good advice from users who do have such a setup.