I have this problem since 2.1 bios.

Almost everytime i boot my pc, its Dead boot (aka only black screen) or normal boot.

no error codes or beeps, nothing.

on dead boot, fans that are connected to mobo spins then after a sec they stop and nothing happens after that. 

Force shutdown aka pillow kill, does not help. 

Only when i shutdown the psu while its on deadboot then i can turn the pc again and its on normal boot.

ive updated everytime i see bios update, but never helps.

my psu/ram/gpu/ssd(didnt try hdd one)  works well on other mobos

i can oc, but only to 4.6 (stupid lotto) on 6700k,

im running 16gb of G.Skill 3200mhz(stock), 1080GTX at stock and cpu on stock speed.

can run any burn in test 24/7 (stress tested for 2days tho no problem heat or otherwise)

but this Roulette boot, i want it gone dont know what to do.

any ideas`?