What to do if Post does not start?

Question

Iron

Lived for a couple of months with the problem of turning on the PC.
To turn it on, I had to connect either another hdd or a cooler.
After that, the indicators on the keyboard blinked, the monitor left the standby mode and the normal PC boot began.
But today this number does not work anymore, the power light on the system unit is on, reset does not even blink, the monitor is in standby mode. That I just didn’t connect to it all the same picture.
The indicator on the switch is lit that the computer is online, while the indicators near the LAN input are dead on the rear rack, the optical SPDIF is also off, but there is power via usb.
Mother 970 Extreme3 ​​R2 ASRock

Answer 1

1. Replace the PSU.
2. Does not help - replace the motherboard ...

Answer 2

There may be several options:
1. Contacts of the memory or video card (you need to remove and insert the memory back and into the card a couple of times carefully)
2. Reset Bios (remove the round battery on the motherboard for 10-15 minutes)
3. Memory either in . the card is faulty, try to replace it with a known good one
3. The power supply is faulty, try to start with a known good one
4. The motherboard is faulty

Answer 3

Increase the power of the PSU

Answer 4

1. Turn off the power (completely, everything from the outlet)
2. Replace the BIOS memory battery (sold at any union-printing stall or the like) or in a computer store
3. Reset the BIOS (how to do this, read in the context of your motherboard such as "how to reset bios with the name of the motherboard"
4. Enable.
Judging by the symptoms, this should be enough.
If it does not help, then check the database and the mother.