HP ZBook Studio x360 G5 video output and TB3 lanes question

[ishraqiyun77]

Looking at one of these and had a few questions. 

I have a ThinkPad X1 Extreme where I disable the dGPU in Ubuntu because it really doesn't get used and causes more heat / fan noise. Due to how was it was designed, the HDMI and TB3 go through the dGPU and I lose the ability to use external monitors when it is disabled.

I'm trying to find out if the HP ZBook Studio x360 G5 with a dGPU has this same issue or if the HDMI and TB3 video go through the iGPU as well. That way HDMI and TB3 would still work if the dGPU is disabled.

I've read conflicting information: one thing says you'd need to go with a model having absolutely no dGPU, just iGPU, to accomplish this; another thing says, yes, the HDMI and TB3 video go through both the iGPU and dGPU.

Can anyone confirm?

Thanks!

[Huffer · Accepted solution]

I am not sure what you have going on your Lenovo with Linux but the idea that external ports only "go through" one video chip in a hybrid video system is not quite accurate. You are probably using a very basic graphics driver for the integrated video in Linux. HDMI and Thunderbolt external graphics will work fine whichever video is active on the Zbook Studio x360 G5. 

[ishraqiyun77]

Well, not all laptops are design such that ports go through one chip or another, but the Lenovo certainly is and it really isn't related to Linux so much. You can hook it up to an external monitor in Windows, then turn off the dGPU (GTX 1050 Ti) off in Device Manager, and the external monitor will no longer receive an video input through the HDMI or TB3. So in the case of the X1E, it appears the external connectors only go through the dGPU. This may not be the case for other laptops, which is what I'm trying to dileniate so I can avoid in the future.