2nd monitor turned on for a split second, shows the Ubuntu logo, and then stays blank

I've just recently reinstall Ubuntu for works(Dual-booting with Windows 11), last time when I installed(dual-boot with Windows 10), 2 monitors works fine, they even keeps turning on on startup. But now with this installation, I can't get the 2nd one to work.

Problem: It will turn on, show the Ubuntu logo for a split second(the main monitor doesn't show the logo), and then turn blank/ black and stays that way.

Setup:

• Main monitor plug into Nvidia GPU(HDMI) and 2nd one plug into Intel GPU(HDMI port on motherboard)
• CPU: I5 10600, Main: Asrock B460M Steel Legend
• Ubuntu fresh install with TPM, secure boot disabled, SGX disabled(if its help)
• GPU driver: nvidia-driver-470 (proprietary, tested - due to works, I can't use another driver version because of kernel compatibility, or at least I think I can't)

At first, I can't get the 2nd one to turn on at all, after following this guide Guide (sorry I can't get the correct reply) disabling Nvidia KMS, it gets to the state I've mentioned above.

So far what I've check are

Xrand

DVI-D-0 disconnected (normal left inverted right x axis y axis)
HDMI-0 connected primary 1920x1080+0+0 (normal left inverted right x axis y axis) 521mm x 293mm
   1920x1080    144.00*+ 120.40   119.98   119.88   100.00    60.00    59.94    50.00    29.97    25.00    23.98  
   1680x1050     59.95  
   1600x1200     60.00  
   1600x900      60.00  
   1440x900      59.89  
   1400x1050     59.98  
   1280x1024     75.02    60.02  
   1280x960      60.00  
   1280x720      60.00    59.94    50.00  
   1024x768      75.03    70.07    60.00  
   800x600       75.00    72.19    60.32    56.25  
   720x576       50.00  
   720x480       59.94  
   640x480       75.00    72.81    59.94    59.93  
DP-0 disconnected (normal left inverted right x axis y axis)
DP-1 disconnected (normal left inverted right x axis y axis)

Nvidia

NVIDIA-SMI 470.82.00    Driver Version: 470.82.00    CUDA Version: 11.4

lspci

00:00.0 Host bridge: Intel Corporation Device 9b53 (rev 03)
00:01.0 PCI bridge: Intel Corporation Xeon E3-1200 v5/E3-1500 v5/6th Gen Core Processor PCIe Controller (x16) (rev 03)
00:02.0 Display controller: Intel Corporation Device 9bc8 (rev 03)
00:14.0 USB controller: Intel Corporation Device a3af
00:14.2 Signal processing controller: Intel Corporation Device a3b1
00:16.0 Communication controller: Intel Corporation Device a3ba
00:17.0 SATA controller: Intel Corporation Device a382
00:1c.0 PCI bridge: Intel Corporation Device a393 (rev f0)
00:1d.0 PCI bridge: Intel Corporation Device a398 (rev f0)
00:1f.0 ISA bridge: Intel Corporation Device a3c8
00:1f.2 Memory controller: Intel Corporation Device a3a1
00:1f.3 Audio device: Intel Corporation Device a3f0
00:1f.4 SMBus: Intel Corporation Device a3a3
01:00.0 VGA compatible controller: NVIDIA Corporation TU106 [GeForce RTX 2060 SUPER] (rev a1)
01:00.1 Audio device: NVIDIA Corporation TU106 High Definition Audio Controller (rev a1)
01:00.2 USB controller: NVIDIA Corporation TU106 USB 3.1 Host Controller (rev a1)
01:00.3 Serial bus controller [0c80]: NVIDIA Corporation TU106 USB Type-C UCSI Controller (rev a1)
02:00.0 Ethernet controller: Realtek Semiconductor Co., Ltd. RTL8125 2.5GbE Controller (rev 05)
03:00.0 Non-Volatile memory controller: Silicon Motion, Inc. Device 2263 (rev 03)

kernel version

5.11.0-40-generic

Display setting and nvidia-settings doesn't detect the 2nd monitor Display settings nvidia-settings

More info:

• 2 monitors doesn't have matching resolutions, one is modern FHD and the 2nd is an old monitor with lower res.
• I used converter to change HDMI to VGA, and it works just fine on Windows, also in the previous installation of Ubuntu

There's a few more things that I did test out but my dumb brain just can't remember all of it, please ask me for more info.

P.S: I'm relative new to Linux, so please understand if I'm slow to understand what you're saying, thank you (English is also not my main language, so if the grammar and all doesn't feel right, that's probably why).

Okay, so if anyone suffering from the same problem I had, here's a possible fix.

I've reinstalled Ubuntu completely(20.04.03 LTS, minimal installation and 3rd party drivers). Details:

1. (BIOS) Double check on SecureBoot(I wiped the keys as well), TPM off. SGX enabled
2. Used nomodeset to boot into the system(or else I'll be stuck in a login loop with the 2nd screen working fine and the main screen only has an underscore character.)
3. I change the nvidia-driver from nouveau to 470(proprietary, tested). Not restarting just yet.
4. Install apt-file:

sudo apt update
sudo apt install apt-file
sudo apt-file update

as a possible fix for missing firmware(i915 firmware - in the installation process I noted that Ubuntu spitting this error everywhere so thought I better check up on that)

5. Disable nvidia KMS

sudo nano /lib/modprobe.d/nvidia-kms.conf
(add this line)options nvidia-drm modeset=0(then save it)
sudo update-initramfs -u
sudo reboot

And that's it, as I'm typing right now, the 2nd monitor is on and working fine(and I hope it stays that way). Will update if things goes wrong again, if anybody have another fix, please feel free to share it!