Question Blackscreen for few minutes after booting

[m0r1t2]

Hello everyone,

I hope someone can help me. I have the following problem:
My computer sometimes has startup problems. That means, when I try to start the computer, there is a black screen for several minutes and the RGB on the keyboard does not light up.
Inside the computer, all fans are spinning and all RGB lights are on. After a few minutes (between 2 and 5), my keyboard eventually lights up and the screen turns on, at which point the computer starts booting and I have the opportunity to enter the BIOS.
Therefore, I have no access to the computer after startup, and it has problems starting up because the screen doesn't turn on and I can't get to the home desktop.

So far, I have replaced the following:
-Motherboard
-CPU
-Power supply
-Hard drive
I have also reinstalled Windows and tested my two RAM modules individually.
I have already opened my graphics card and replaced the thermal paste.
I have updated the BIOS, and the temperatures of the CPU and GPU are consistently good.
Once the computer is running, there are no problems, even in games.

My hardware:
Gigabyte X570S AORUS Elite AX (BIOS F6a) (previously: Gigabyte B450 Gaming X)
AMD Ryzen 9 5950X (previously: Ryzen 7 3700x)
AMD RX 6800 32GB CORSAIR Vengeance RGB Pro (2 x 16GB) DDR4 3200Mhz
Samsung 980 PRO M.2 1TB (previously: Crucial P1 500GB)
Power supply: BeQuiet! 850Watt Pure Power 12 (previously: BeQuiet! 600 Watt Pure Power 11 CM Modular 80+ Gold)
CORSAIR iCUE H150i Elite

 

[Colif]

My computer sometimes has startup problems. That means, when I try to start the computer, there is a black screen for several minutes and the RGB on the keyboard does not light up.
Inside the computer, all fans are spinning and all RGB lights are on. After a few minutes (between 2 and 5), my keyboard eventually lights up and the screen turns on, at which point the computer starts booting and I have the opportunity to enter the BIOS.

What the delay could mean is the PC is waiting for something to respond and only after it times out does it continue boot process
What is oldest part of PC? Have you got any hardware attached that has always worked before?
It could be anything, speakers... mice, keyboards.

shame its only sometimes. Any hardware played up or done anything odd recently?

Other thought - do you have any Hdd as they are one thing that if they are dying can slow down boot times.