Why is the second monitor connected to the laptop blinking?

Question

Iron

Hello!
Notebook Acer Aspire 7750G Intel(R) Core(TM) i5-2410M CPU 2.30GHz, RAM 4 GB, 64 bit operating system, Windows 7 Home base
video card AMD Radeon HD 6650M
Second monitor connected via vga, Acer AL1916W monitor, old .
Most often I do not need a second monitor, but sometimes I connect it. Periodically, the monitor goes out for a second and starts working again. Sometimes this leads to the fact that the system loses it, respectively, open windows fly to the laptop monitor. Accordingly, this is the problem. In hardware, I'm not very smart, I always thought that sending a signal to another device should not be "expensive" for a video card. Moreover, this happens with any load on the video card, the frequency also does not depend on the load.
PS I will buy a new laptop at least after the new year, can I help myself with something now?

Answer 1

There was a similar trouble with the hospital, having reviewed the monitor, lamp, cords, as a result there was a problem with the video card, in your case, you can also check it on another monitor and cord when you come to visit. In a separate case, the settings on the external monitor in the driver may be incorrect.
Check on a monitor with HDMI, it is digital, and VGA is analog, this may be the problem.

Answer 2

Is it possible to test and see how this monitor behaves with a different signal source (computer, another laptop.)?
In an old monitor, a power supply unit (dry electrolytes) can be "planted", as a result of which it simply periodically turns off due to a lack of power - it has come across this more than once.

Answer 3