Thanks for the detailed update! I hope it helps people out.

With regard to multiple montors and video cards, I'm not sure there is a "normal" way to connect them, and on my system I have two HDMI switch boxes so I can independently switch monitors/video cards on the fly. The only thing I need to do is close PD before switching, and I don't have to reboot for PD to "see" the new monitor when I relaunch it.

I've also found that it's usually better to run both monitors off of the same card when editing. It's actually possible for PD's About screen to show the nVidia icon but then also show the QuickSync option on the Produce page. Running both monitors from the same card eliminates that disphoric behavior.

I know that Resolve suggests that users set their less capable GPU as the "Display" GPU, and that frees up (?) powerful Nvidia cards to do encoding. (Resove uses the CUDA cores (I think.))

But since I don't have the Studio version of Resove (which uses HA) I can't test that scenario to see how driving monitors from the same GPU affects performance.

However, along with PD15 I do have Magix's MEP 2020, and the MEP I get different results (as in faster encodes) depending on what type of video I am encoding and which GPU I have selected as the "Display GPU." As well as which is selected in Win10's Graphic Settings.

That is with my two displays driven from two different GPU's.

I suppose I will now have to go back and do all my experiments over again, this time with both monitors hooked up to the GTX-1650 Super. (I would do them connected to the Intel UHD too, but on my (cheap) motherboard, there is only VGA and HDMI out. I suppose I can hook up one of the monitors using VGA, but that sounds so low tech, I wonder if it's worth testing?)

I suppose I should compliment someone at Microsoft for making Win10 work so well with two monitors driven by two different GPU's.

Are we having fun yet?

Quote

*AMD CPUs do not have dedicated video encoding silicon on board, so only options 1 and 3 are available, and that does match your description.

AMD does have from a long time a version of accelerated decoding/encoding hardware, and it's called UVD/VCE:
https://en.wikipedia.org/wiki/Video_Coding_Engine
Their latest GPU have switched the naming of that SIP core to VCN:
https://en.wikipedia.org/wiki/Video_Core_Next

Quote I suppose I can hook up one of the monitors using VGA, but that sounds so low tech, I wonder if it's worth testing?)

On my Dell Optiplex, if I select in BIOS the GPU as "Auto", then only the PCIe card is seen (nVidia for example). But If I select "Priority to PCIe", than both the nvidia and the Intel GPU are available in Windows.
Then, in encoding software like the freeHandbrake, you can manually select either of them for the encoding job.

On some other PC's, there is a need of a dummy VGA load, to trigger the Intel GPU. You can buy one from Amazon or... make one:
http://www.geeks3d.com/20091230/vga-hack-how-to-make-a-vga-dummy-plug/

Depending of your CPU generation, it will have more or less advanced capabilities. I know that my gen 4 i7 (Haswell) is not very capable, see here the Intel Quick Sync capabilities, based on the generation of CPU/GPU:
https://en.wikipedia.org/wiki/Intel_Quick_Sync_Video#Hardware_decoding_and_encoding

On my new (used) Dell, I have set the UHD to be the Primary video GPU, and so when the computer boots, the BIOS info displays on my second display. Once Windows is running, the monitor driven by the GTX-1650 Super becomes alive. So Windows 10 sees both.

The 8th and 9th generation Intels have the UHD 630. I just read the other day that 10th gen Intels will have an iGPU that will do more.

Quote AMD does have from a long time a version of accelerated decoding/encoding hardware, and it's called UVD/VCE:
https://en.wikipedia.org/wiki/Video_Coding_Engine
Their latest GPU have switched the naming of that SIP core to VCN:
https://en.wikipedia.org/wiki/Video_Core_Next

Thanks for the correction. Do you know how PD shows that option on the Produce page? It's QuickSync for (U)HD Graphics and Hardware video encoder for nVidia. I can go back and edit that post once I know what the correct terminology is.

I have a laptop with i7 processor running Windows 10 and PD14. The PC has an Intel HD graphics 4600 and a Nvidia Geoforce GTX 960M. The Geforce driver version is the latest ( 441.66 ). I have tried the "Graphic setting" trick and got funny results :

1) In the Nvidia control panel, it shows that the PD is still using the integrated graphic card and not changeable ( grey out )

2) Nvidia GPU activity windows shows that the application pdr.exe is running on the GPU after PD is launched.

3) When I play a video in PD, the task manager shows that the Intel GPU is working, the "3D" window is showing 7% for the Intel GPU and 0% for the Nvidia GPU

4) When I produce a video ( 1080p 50 fps, 50 Mbps H264 ), the "3D" window of the Intel GPU is showing 1% . Nvidia GPU is 0% ( how come its so low BTW ? )

So in practice the Nvidia GPU is still not being used. Just wondering if I have missed something.