Cpu1 cable caught fire

[in3rdgasm]

Upgraded my CPU and motherboard and rebuilt the whole rig inside of a new case, when I turned it on for the first time I heard a cackle and smoke started coming out of it and one of the two 4pin cpu1 power cables had caught fire and burned. Any idea why this happened and what I need to do next to solve this?

 

[Shektron]

Can you list the full system specs please? Did you connect all the CPU power connectors, in case there were more than one CPU power connectors?

 

[in3rdgasm]

Nvidia GeForce 1080ti
I7 6700k
Asus LGA1151 H170 atx pro gaming mobo
Corsair vengeance 16gb ddr4
Evga supernova nex750g psu
Corsair hydro series h80i v2 liquid CPU cooler
Samsung 850 evo 500gb ssd
1tb disk drive

And yes I plugged in both 4pin CPU1 power connectors and one of the two was the one that bursted into flames

 

[Shektron]

There could be a lot of things at fault here - the power supply, the cable, the motherboard, the CPU, or even the BIOS. I doubt it's the BIOS, since it happened on first boot. All the other things could have been a problem. If nothing else has been damaged, I suggest you buy another CPU power cable and try to run the system again, and hope that it was just a faulty cable.