Question MOBO LED reads yellow error please help

mrjohan901

Prominent
Jul 26, 2017
3
0
510
Ryzen 7 2700
Rx 5700 xt
Hyperx 2666 2x8 ddr4 ram
Seasonic focus 650w 80+gold
Asus strix b450-f gaming
Phantek 400

A friend of mine bought this and he asked me to help him build it. Im decently sure that everything is in the right place as ive done similiar before.
Everythinf has power and all the fans are spinning but theres a yellow light on the motherboard and it doesnt boot at all. So i checked the ram becouse tgat was what the yellow LED said. Switched slot/switched to one stick/and just generally tried every postition. If we have one stick in the 3rd slot the LED briefly turns red then back to yellow.
I would really appreciate tips and fixes to make it work as its very annoying