Small lines appear on the screen, for what reason is unknown.
If these 'dashes', regardless of the manipulations carried out (watching video, surfing the Internet, playing), then, unfortunately, with a high degree of probability, the reason is a technical malfunction of components (video card and motherboard) and / or poor contact of the cable connection (if it is not a laptop / netbook).
The first step is to check if the cable from the system unit to the monitor is firmly connected.
Try, if possible, to connect the system unit to another monitor or TV, and if the problem persists, then the option with a monitor can be excluded.
Accordingly, there will be two 'patients' left – the video card and the motherboard. An external examination may not help, so clean the contacts and the entire system unit from dust and, if possible, check these components on another computer or take them to a service center. You should not buy new ones prematurely.
If the problem is of a periodic and selective nature, then the reasons may be software, for example, incorrectly installed drivers. But it should be repeated that the problem is almost certainly a physical one.
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Andrey PonomarevProfessional assistance in setting up, administering, reinstalling any programs and operating systems of the family Windows.
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