Strange Dots On Monitor

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I forgot to write that the dots start to appear only inside “Desktop Environment” (in my case Gnome), not for example in grub/bios. Today I
tried to install ubuntu 16.04 and the green dots appeared there too (in Unity).

6 thoughts on - Strange Dots On Monitor

  • Yves thank you very much for your help, today I tried newer drivers but the problem persists. So I think it is hardware problem. Since the laptop is still in warranty I will probably contact the manufacturer. My only worry is that they would not accept it since I am running Linux (the laptop came with Windows – and I am not sure if the problem would be also present on Windows). Do you think there could be some issues with warranty service in this case?

    Thank you very much and have a nice day.

  • To me it sounds like hardware problem. I can imagine that to happen if the chip was overheated. I would check if the fan on video card is not stuck, and if there are cables or anything that could get into fan and stop it. This basically is about figuring out what happened.

    If dots are periodic, and are of “clean” color (i.e. RGB or combination of any pair of these at arbitrary intensities), then these look like trouble with some bus drivers inside video chip related to internal data interconnect. If you fry ATI video chip, the pattern is rather simple
    (periodic). I have seen also periodic pattern on older nvidia cards after they had been overheated. In my experience it is much easier to damage by overheating nvidia based card than ATI based, but I have seen more or less modern ATI card fried as well.

    Warranty: I wouldn’t worry about which system the machine was purchased with and under which hardware failed. I’ve dealt with a lot of failed hardware, and usually hardware vendors will not tell you that you damaged their hardware because you run wrong system or wrong driver. If I were told that by hardware manufacturer (which I never was), I will immediately reply that if hardware was connected to bus resembling specs, no matter what signals are sent to hardware, it will not be damaged. It it is damaged because of that, then hardware was poorly designed from electrical engineering point of view. And this is indeed true about all rather trivial things such as computer components.

    What hardware vendor is entitled for is: have “faulty” hardware tested under the system the computer was sold with. That is: before even going to warranty replacement, do the test with Windows, and confirm the failure. They may ask you go through variety of steps they have in their diagnostic schedule, follow what they tell, and report what you observe. They really appreciate if you report what you tried when you start talking to them, meaning that you put effort in solving it, but they will need troubleshooting according to their procedures done as well.

    Good luck.


    Valeri Galtsev Sr System Administrator Department of Astronomy and Astrophysics Kavli Institute for Cosmological Physics University of Chicago Phone: 773-702-4247

  • If laptop was purchased with Windows 10 (some incarnation like
    “home”,…), then when you will install Windows 10 the same incarnation on it, it will read its “authorization code , registration number or whatever prevents it from telling you “buy/ register… from UEFI. If you switched boot from UEFI to BIOS when installing Linux this will not work, but just switch boot back to UEFI before installing Windows, and registration will auto-magically work for you.

    I hope, this helps.


    Valeri Galtsev Sr System Administrator Department of Astronomy and Astrophysics Kavli Institute for Cosmological Physics University of Chicago Phone: 773-702-4247

  • Thank you very much for your help,

    I installed Windows as you advised, tried few gpu tests, everything was running fine. To be honest I was afraid that I would not be able to reproduce this problem on Windows, but after running few Dell SupportAssistant tests for various hardware components, it found out that system memory failed multiple tests. So the cause of this problem is probably broken RAM. Since the laptop is still in warranty Dell sent me new parts. Thank you very much for your help again, I really appreciate it :)

    After new memory arrives, I will let you know if it solved the problem.

    Have a nice day Vych