Question b450 red cpu light wont boot

[rentico]

Hey guys need some help

I have a gigabyte aorus b450 elite (new)
when I try to power it on all fans and gpu start spinning but it comes up with a red cpu light, the cpu fan is also plugged in and spinning, have tried different coolers also

i have tryed a ryzen 3 1200 and a ryzen 2600 in the board, two differnt psu, every ram slot, clearing the cosmos
I have also tried with different gpus
when i put power to the board all the rgb on the bord flashes for a split second, some times red some times white, tho every time still red cpu led

there is many post about this isue on google but no one has an answer

 

[rentico]

thanks in advance

 

[rentico]

also I have tried both cpu in another mobo and they both work fine

 

[popatim]

If you've already tried breadboarding the system outside of the case and are sure you have all the correct powersupply cables installed into the correct locations (mainly the 24pin plus the 8pin CPU/EPS) then it would be a motherboard issue.