Hello! I built a new system last May (Asus X99-A mobo, i7 5820K cpu, Be Quiet DPP P10 850W psu, 2x MSI 970 gpu in SLI, 32GB Corsair 2400 ra, Samsung 850 Pro ssd) and it's been working perfectly fine since then, until last night.
I rebooted it at 2am, and after power-down it didn't come back up...