Questions and problems about the motherboard on an HP pavilion dv6 2121-er laptop?

Question

Do it yourself

The situation is as follows: The
laptop (HP pavilion dv6 2121-er based on i5 and nvidia m230 video chip) stopped starting. Namely: when the power is turned on, there is no video stream on the monitor, there is no image (even BIOS loading). The cooler starts up, the LEDs (touchpad) light up, the monitor is powered (the LED backlight is on at the back of the monitor). No sound or light signals. If you unplug/plug the monitor and turn on the power. The monitor is being checked (test, cyclically). When connecting other monitors to the HDMI/VGA connectors and starting the computer, the result is the same, there is no image. Sometimes when you turn it on, it shows a black background. If you stick out the RAM, then when you turn it on, the indicator of the Caps Lock key gives 3 light signals, which corresponds to problems with the memory module. Tried to remove the battery, but the result is the same.
Questions:
1. What's the problem? What else should be checked and in what ways?
2. Where on the mat. board to find its model?
3. Advise where you can find the model of this mat. fees? What should you pay attention to when buying?
4. Basically, dv6 laptops were produced based on AMD (weaker configuration), will such a mat suit me. pay? Can I change the processor to my i5 and the video chip to Nvidia on an AMD-based board?
5. Where / where can I sell a non-working mat. laptop fee?

UPD:
The problem was solved in the service center. The video chip has been replaced. Repair cost 5500 rubles.

Answer 1

1. The vidyuha died
2. The second photo, there "... Rev ..." is written
3. It's not worth buying
4. No
5. In any service for pennies.
I will explain the 3rd point - all (well, 99%) used ones will be with dead vidyuhi, just warm and temporarily functional.
You are unlikely to find a new one anywhere, just like a replacement GPU chip.

Answer 2

My HP Pavilion dv7-5000er is dead. The symptoms are almost the same. Only caps gave 5 signals. Wrong on video. Took it to a service center. They said that the north bridge is to blame for everything, the price for all is 7 sput. I didn't change.