Why does the computer not turn on after the first assembly?

Question

Iron

Greetings!
Thanks in advance to everyone for the replies and recommendations. No curtsy - straight to the point.
I bought and assembled it myself, I can’t start the computer
Build amd am4:

• 
  
• Motherboard: ASRock Fatal1ty AB350 Gaming K4
  
• Processor: AMD Ryzen 5 2600X OEM
  
• RAM 16Gb DDR4 3000MHz G.Skill Aegis...
  
• Case DeepCool KENDOMEN Titanium Black
  
• Power Supply FSP PNR 500W [ATX-500PNR]
  
• Cooler DeepCool GAMMAXX300
  
  
• Nvidia geforce 1050ti
  
• Samsung SSD with Windows already installed
  

I understand that not all points here are important, but this is done just in case.
Now more about the problem:
I turn on the power > the computer starts up > the monitor does not show anything, that is, a black screen. All fans are working except for the top ones (apparently I didn’t connect them, but this will be seen further in the photo) > the computer remains on for about 10 seconds and then reboots. The cycle is over and it is endless (this is the cycle, right?). I noticed that if I press the power button for a long time, the computer still turns off.
Description of the assembly process + my guesses
Actually, there is not much experience in assembly. Before that, I just dug into my old and already assembled computer 8 years ago. Now I am writing from it.
When placing an order, I was told that the motherboard would need to be flashed. I did not attach much importance to this, since I expected that the BIOS was already on the mother and it would only need to be updated. Perhaps, nevertheless, there really is no bios on the mother and therefore it does not start, how can this be checked? In the meantime, I will describe how I collected and perhaps somewhere you will see an error.
Along the way, I saw and read a lot of guides on how to assemble a computer. I followed the guide strictly, but obviously there is a mistake somewhere.
I checked everything several times:

• 
  
• I checked the power supply from the front panel many times - everything is according to the scheme, as in the instructions from the motherboard. Below there will be a photo, although only the upper part of the connection, but I connected it according to this scheme:
  - the first two from the top left are: Power LED + and Power LED -;
  - 3rd and 4th pin from above is occupied by Power SW;
  - 1 and 2 from the bottom left is HDD LED; 3 and 4 from the bottom is Reset
  
• The processor entered smoothly and without problems - closed tightly.
  
• The cooler is, of course, peculiar, but still managed to fasten it tightly.
  
• I inserted the RAM tightly, through one. The RAM fits the motherboard. Memory 3000 and mother supports up to 3200
  
• Several times I checked all the power from the power supply to the motherboard. And the power of the motherboard itself, and the power of the processor, and the power of the video card
  
• The SSD was also connected correctly - one cable from the power supply, the second to SATA 3 on the motherboard
  
• I also carefully connected the power from the front panel: sound in HD audio, USB 2.0, USB 3.0, fans. The only thing I did not understand is how to connect the top fans. The front ones work, the rear one does, but the top ones don't. Perhaps there is an error here.
  

I am attaching pictures of the assembly, but without the included video card and SSD. Otherwise, I will not be able to answer from the second computer.

Answer 1

When placing an order, I was told that the motherboard would need to be flashed. I didn’t pay much attention to this, because I expected that the BIOS was already on the mother and it would only need to be updated.

Bios on the mother, of course, is already there. But in order to update it, you need to have a mother. And she, judging by the words of the seller, with the old bios, and the new process will not start. That is, the algorithm is this - take an old percent from a friend, which is guaranteed to start (look at the versions at https://www.asrock.com/mb/AMD/Fatal1ty%20AB350%20G... , pay attention to "Note1: AMD Ryzen 1xxx series CPUs are able to boot up with all BIOS versions."), start a mother, flash a new BIOS (look in the same place, you need 4.70 or higher, download from here https://www.asrock.com/mb/AMD/Fatal1ty% 20AB350%20G... ), put back your percent.

Answer 2

Perhaps there really is no bios on the mother

It doesn't happen. :) I.e. theoretically, of course, it can be torn out of the mother (this is a small chip, it is not soldered, but inserted into the socket), but mothers are not sold without a BIOS, because nobody needs it. There is a BIOS (actually not a BIOS, but an EFI, but nobody cares), it's just that the processor was released later than the motherboard, and the BIOS does not know how to work correctly with this particular processor. To update the firmware, you need to install some older processor, update it, only then you can return the new processor to the motherboard and you can start it.

Answer 3

It’s easier to take it back to the store, they will update it in a day or two (well, if there are no friends with the old version of the processor).

Answer 4

If the monitor does not respond, then the problem is in 4 places, the mother, processor, memory or video.
Act from a small one, collect only the mother + percent + video, and turn it on, if everything is ok, then connect one stick of RAM and turn it on, maybe one of the sticks does not work or they are not compatible with the mother

Answer 5

The reasons may be +100500
1. The problem with the PSU. Try a PSU from a working computer
2. Memory problem. Try the memory on another computer
3. Problem with the video card. Throw out the discrete, try to run with the built-in
....
100500. The problem of incompatibility of the motherboard and processor. No wonder the store said that the BIOS needs to be reflashed. On the other hand, in any case, the computer should start, and the BIOS will have something like Unknown CPU.
Start by removing everything, leave the motherboard and processor bare, connect only the power button or close the contacts with a screwdriver (just be careful). NECESSARILY!! check that the processor is installed correctly. If the CPU cost is crooked (I have seen this many times), align the legs or buy a new one if the legs are broken off.
When you turn it on, you will hear a signal of lack of memory (a good sign) otherwise your battle is over, try to exchange the motherboard and / or CPU under warranty.
If you heard (in the presence of a tweeter) saving long beeps, or maybe you saw a "happy signal" if there are POST indicator lights, install ONE!! memory bar. If everything worked for you, you can breathe a sigh of relief and smoke.
Then everything is simple. Put the second bar of memory, SSD, video card. Of course, at each stage, you check the performance of the system.
You also need to understand that "already installed Windows" may not work or work, but with a bunch of problems. It is worth not being too lazy and reinstalling.
PS Before buying all this junk, you should know that ASRock is an experimental division of ASUS. They create all sorts of monsters and sell them cheap. If the idea takes root, then it goes into the main line of ASUS products. ASRock products are bought either by "urban madmen", those who like to pick iron and measure the number of parrots in tests, or naive simpletons who peck at a low price. You should also know that a bunch of AMD CPU + AMD GPU has a number of advantages over AMD CPU + Nvidia GPU

Answer 6

it was necessary to take asrock b450.
When I collected it myself, I also chose between these mothers and a couple of others.
for the price it would have turned out the same, but without dancing with a tambourine, because she is sewn right away.
Well, now go to a friend / acquaintance and mother.
or to a service. stitched, if I'm not mistaken, for 200-300 rubles.
ps: rather, there is not a bios, but ufi, but who cares ...