Crowzer

Managed to solve my issue !
I removed every components from motherboard except for MB/CPU power, the rest were all removed (fans, SSD, USB, Audio, etc...)
 
Then, I tried to flash bios with USB key and instead of during 4 mins as before it lasted for 8 mins. I put back CPU and RAM but I got error code some error codes. I tried to unplug and plug back RAM and it seems fixed.
 
At this state PC didn't boot because of error 02 code. So I look on internet and someone said "you have to plug keyboard" and I did that and I was able to boot as usual.
Crazy...

I found two methods that work to help getting the motherboard back to normal:
Clearing CMOS will make it possible to boot on the pc afterwards but you will lose all personalized settings you did in the BIOS, ex. PWM Fans and RAM frequency settings.
Turning the power supply unit off and back on while the pc is turned on will make it possible to boot the pc normally and no settings are lost.
The above information was stolen from the website'
Code 00 means that even POST is not possible and indicates direct fault with BIOS / motherboard or CPU.

Unplug everything but cpu, ram, and power. Do the bios update again. Let it sit there for 10 minutes. It should restart by itself. 

As I said I have a high-end powerline but from 2017, so maybe there are ones more efficent nowaday ?
If not, my only remains option is WiFi repeaters. What's the best ones for through walls (if it exists) ?
 
That's why I asked here, maybe someone is in the same situation as me and found a solution since.

Hello,
 
Because my house is quite atypical, I stuggle for ages to have a stable and high connection speed. My router delivers 200 Mbps down and 250 Mbps Up (measured with an app with my iPad).
I cannot use an ethernet cable and I cannot move my PC.
 
For now, I use a powerline kit. Working fine but it really cripples my internet speed connection. Powerline model is TP-Link CPL 2000 Mbps from 2017.
I juste tested and it show around 76 Mbps down and 61 Mbps up. And one big problem is the speed is not stable: sometime the speed goes like 50 Mbps down and 30 Mbps UP. It varies too much.

So I'm thinking to buy some wifi repeaters, the internet router is not too far (around 15 metters) but there are 2 thick walls between this latter and my PC.
 
Here a basic drawn :

 
 
I mainly use internet for download stuff and heavy online gaming.

Do you think wifi repeaters will be enought ? Can I use 2 ?
Or maybe there is an another solution ? Like other good powerline ?
 

Should be replaced because of Group Regulation.
No need to go 600W again, get a better one this time. Pure Power 10 is OKish, but better get a Straight Power 11, Bitfenix Whisper M (or Formula).
550W is fine, probably even 400-450W.

My Ryzen 2700X with Asus Performance Enhancer LvL 4 and with my almost-3-years old RAM (HyperX Fury 2666Mhz OC to 3000Mhz CAS16).