Ubuntu 20.04 VGA is not accelerated with nvidia gpu

I am running ubuntu 20.04 on lenovo yoga slim7 laptop which is loaded with nvidia 350M graphics card. I add ppa and apt installed nvidia-470 driver which is the latest one however GPU does not seem to be utilized for desktop GUI rendering as I feel delays in any screen input even for terminal.

Here is what the settings > About page look like.

enter image description here

I checked lspci to find VGA controller but could not find nvidia here.

$ lspci | grep VGA  
00:02.0 VGA compatible controller: Intel Corporation Iris Plus Graphics G1 (Ice Lake) (rev 07)

and only find

$ lspci | egrep -i "vga|display|3d"  
00:02.0 VGA compatible controller: Intel Corporation Iris Plus Graphics G1 (Ice Lake) (rev 07)  
30:00.0 3D controller: NVIDIA Corporation GP107M [GeForce MX350] (rev a1)

Additional info

$ lspci -k | grep -EA3 'VGA|3D|Display'
00:02.0 VGA compatible controller: Intel Corporation Iris Plus Graphics G1 (Ice Lake) (rev 07)
    Subsystem: Lenovo Device 3a34
    Kernel driver in use: i915
    Kernel modules: i915
--
30:00.0 3D controller: NVIDIA Corporation GP107M [GeForce MX350] (rev a1)
    Subsystem: Lenovo GP107M [GeForce MX350]
    Kernel driver in use: nvidia
    Kernel modules: nvidiafb, nouveau, nvidia_drm, nvidia

Is there a way to enable GPU for VGA controller?

Solution 1:

There has been a discussion regarding this issue here https://bugs.launchpad.net/ubuntu/+source/linux/+bug/1937072

Problem is caused by PSR in ubuntu. To disable PSR, open /etc/default/grub with editor and add below line

GRUB_CMDLINE_LINUX_DEFAULT="i915.enable_psr=0"

If there is GRUB_CMDLINE_LINUX_DEFAULT, add # in front of the line.

Save and exit.

Enter "$ sudo update-grub" and "reboot"

To check if PSR is enabled by entering

$ sudo cat /sys/module/i915/parameters/enable_psr

should return “0” zero.

Formerly, it gave me “-1”.