Flickering screen and system is shutting down

I installed zorin os on my old pc 2 months ago. The screen was flickering a little but it was running ok. Yesterday it start to shut down as soon as i open any application.

Are you using AMD or Nvidia Graphics card?

No im not using graphic cards

Are you able to boot into any desktop at all or to the TTY terminal screen?

Yes. It only turns off whenever i try to open any applications like files google chrome

Can you open terminal (keyboard shortcut ctrl+alt+t)?

Yes. Only terminals working

Can you open terminal and run:

sudo lshw -C video

I log on to my pc and now its working except the trembling screen now and then.

Let's focus on the flickering since the other issue may recur.

Well it was always there since i installed zorin os

Is this a notebook? (I refuse to use the term laptop as it engenders improper use). If so the screen inverter may be failing and you did say it was old. My good lady's machine, a desktop flickers on Apps opening, mainly SoftMaker Office, and it is from 2006 running MX-Linux, 2Gb RAM and 256 Mb 8x AGP graphics. If you know the specs of your machine that might help.

Its not a notebook it has 3.4gb ram, intel 945G graphics. I noticed thats the the screen flickers a little whenever i click on the screen or open any application. For some time i was using only 1 ram in my computer. i wasn't having this problem then.

See if this helps:

iommu=igfx_off

" 1. Open a terminal application
2. copy sudo nano /etc/default/grub in the terminal

  1. press Ctrl + Shift + v to paste
  2. Find the line starting with GRUB_CMDLINE_LINUX_DEFAULT and append intel_iommu=igfx_off to its end
  3. GRUB_CMDLINE_LINUX_DEFAULT="quiet splash intel_iommu=igfx_off"
  4. press ctrl + x, then y, followed by enter to save and exit
  5. run sudo update-grub in the terminal
  6. reboot

You can confirm your modifications after the reboot by running cat /proc/cmdline and looking for the parts you added.

Hope that helps and feel free to reply with any more questions you have."

[Source: https://www.reddit.com/r/linuxhardware/comments/exovc6/comment/fgciyte/]

It did not work.

How old is the screen? Have you tried a different monitor cable?

Its not that old. It works fine when i lower the screen resolution

Are you using Fractional Scaling?

No, i just changed the resolution to 1680x1050

In terms of system shut down, this might help you find the cause: