The motherboard beeps about a video card malfunction, what should I do?

Question

Iron

A friend built a new computer. I came, we put ten on the computer; the installation was not painless. There was such a problem that when you press the button it did not go into the BIOS. I solved the problem by resetting the BIOS RAM (close 2 pins with a screwdriver) and setting the default settings there. but there is another problem here. after this reset, the monitor began to say that there was no signal, and the motherboard beeped 1 long-3 short beeps, which means there were problems with the video adapter in this BIOS. I had to take out the vidyuhi and use the integrated one. everything is fine with it, then they installed the tenth Windows, put firewood on the card; they inserted the card, after setting the "dual boot" of video cards in the BIOS (as I understand it, it allows you to use both that and that GPU at the same time - if it gives a discrete error, then it uses the integrated one); Windows clearly identifies it
The problem is that the video card is not working. For myself, I identified several possible situations:
1) The video card was initially problematic - before the BIOS reset, the priority was on the integrated one, we just didn’t notice it; after the reset, the priority moved to an external video card, but due to its problem, only no signal is displayed on the monitor and the motherboard beeps .
2) The problem is in the BIOS settings - before the reset, the priority was on the external vidyuhi and, due to the correct settings, everything was fine; after resetting the settings, the vidyuha refused to work normally because it was uncomfortable with the default settings.
3) The video card was physically intact before resetting the BIOS RAM, it became faulty after - I don’t really believe in it, of course, because no one seemed to bend it in half, didn’t bend it or threw it on the floor, but suddenly ...
4) Some kind of incompatibility with other components - the motherboard, for example, a power supply, or a friend just installed it incorrectly (although it seems like Windows recognizes it) - I don’t really rummage around in hardware, because all my life there were laptops where you don’t need to change the hardware, Yes, and mothers were there with a legacy bios, and here is a brand new one, UEFI;
In short, tell me what could be the matter and how to fix it - tomorrow, March 4, I plan to visit him again and try to apply various recommendations.
Motherboard asus prime b360m-k;
vidyuha asus geforce gtx 1050 ti;
I don’t remember the rest of the components (I just remember the PSU 600 watts power)

Answer 1

sorry for asking such a stupid question))
It turned out that my friend and I were two blind suckers and connected the monitor to the motherboard (that is, the integrated video), and not to the card itself :((
thanks to everyone for the answers, we disagree))

Answer 2

Did you connect the 6pin power cable to the video card? What cable did you use to connect the monitor to what port?

Answer 3

It makes sense to check the power connection to the card - all connectors must be inserted, how many of them are there on the video.
Also: in the BIOS, be sure to set "auto" in the parameter for using video cards - otherwise you will have to look for and insert a working card if ti is dead.

Answer 4

The standard scheme in this situation is to carry the video card to a friend and put it in his computer, thereby checking the performance of the video card, then take a working video card from a friend and put it in your computer, thereby checking the performance of your motherboard.