Laptop's performances are low considering that it's running Manjaro

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44

I don’t have GRUB while booting up laptop.

EDIT: Is the kernel changing necessary?

45

yes it is, since the open source nouvea drivers work better with the 5.10/ 5.4 kernels…
for the grub menu:
kate /etc/default/grub
and change this line to look like this:
GRUB_TIMEOUT_STYLE=menu
then save the file and run this:
sudo update-grub

then uninstall the bumblebee:

sudo mhwd -r pci video-hybrid-intel-nvidia-390xx-bumblebee

install the video linux:
sudo mhwd -i pci video-linux

install the kernels:
sudo mhwd-kernel -i linux510
sudo mhwd-kernel -i linux54

reboot and in the grub menu/advanced options select the 5.10 (not the fallback one, the normal one), and test with it… if you have some issues with it, switch to the 5.4 and test with it…

just noticed that you are on raid:

this can also cause issues, so in bios switch from RAID to AHCI … but maybe a clean install on AHCI would be better…

46

You mean to set it to AHCI then to reinstall Manjaro? Also, I don’t have GRUB while I am booting up laptop. I have HP logo then Manjaro login screen appears.

EDIT:

https://ibb.co/kSzgGLy

In BIOS I found I that I am not using RAID. And I dont have option to switch to AHCI anyway.

47

for the grub menu i gave you instructions:

then continue with the steps above: uninstalling bumblebee, installing video linux + kernels, rebooting and switching to 5.10 …

well if you can switch to ahci in bios, thats nothing we can do, so forget about it…