nvidia-prime breaks Intel display driver?

[burntex]

Hi, Maybe you can help. I have had this issue for over 1 yr. I am running a desktop Mint 20.3 with a dual monitor setup with an Intel UHD 630 and Nvidia GT 1030. The second monitor is an LG 4K TV. I have an HDMI switch to switch The LG to the Intel motherboard port or the GT 1030 Card. When I am in Nvidia on-demand with the GT 1030 connected to the LG things wotk as expected nut when I run in 'power saver' Intel only mode with the LG switched to the Intel port I can only get the displays to work in mirror mode at 1080. If I run the displays in extend 1080 mode the LG is blank except for the cursor. With LG set to 4K the main 1080 display has my lower panel rise to the top with nothing else displayed and again the LG is blank.

The reason I think this may be an nvidia-prime problem is if I boot from a Mint 20.3 drive from my laptop with only a UHD 620 (No Nvidia hardware or drivers) on the same Desktop system the dual monitors work fine in extended mode. Also everything works on same desktop with Windows 10.

Any thoughts? Thanks.

inxi -Fxz System: Kernel: 5.13.0-35-generic x86_64 bits: 64 compiler: N/A Desktop: MATE 1.26.0 Distro: Linux Mint 20.3 Una base: Ubuntu 20.04 focal Machine: Type: Desktop System: Gigabyte product: H370M-D3H v: N/A serial: <filter> Mobo: Gigabyte model: H370M D3H-CF v: x.x serial: <filter> UEFI: American Megatrends v: F13 date: 06/05/2019 CPU: Topology: Quad Core model: Intel Core i3-8100 bits: 64 type: MCP arch: Kaby Lake rev: B L2 cache: 6144 KiB flags: avx avx2 lm nx pae sse sse2 sse3 sse4_1 sse4_2 ssse3 vmx bogomips: 28800 Speed: 1377 MHz min/max: 800/2200 MHz Core speeds (MHz): 1: 1377 2: 1575 3: 1410 4: 1422 Graphics: Device-1: Intel 8th Gen Core Processor Gaussian Mixture Model vendor: Gigabyte driver: i915 v: kernel bus ID: 00:02.0 Device-2: NVIDIA GP108 [GeForce GT 1030] vendor: Gigabyte driver: N/A bus ID: 01:00.0 Display: x11 server: X.Org 1.20.13 driver: modesetting unloaded: fbdev,vesa resolution: 1920x1080~60Hz OpenGL: renderer: Mesa Intel UHD Graphics 630 (CFL GT2) v: 4.6 Mesa 21.2.6 direct render: Yes