What did i break?

[Post Hoc]

So installing a nzxt hue, i used a sata power cable from a different psu (modular) and turned on my computer. The only thing that turned on when i did this was my nzxt hue, and the RGB mobo led. No case fans turned on, no graphics card. After that i unpluged the incompatible cable and googled. I found this (https://www.reddit.com/r/NZXT/comments/5dqcg2/the_nzxt_hue_did_not_kill_my_pcs_public_apology/)

My Computer will not turn on at all, not for a second. So i tested my PSU, Grahpics card, and Hard drives in another computer, they all work. My mobo "power" led (Asus z370 e gaming) will blink but it will not turn on and i dont know how to test my cpu (i5 8600k).

When all this happened i did not see any sparks, smoke, no smell, and no sounds. Is my mobo dead or my cpu dead, or both?

cheers and thanks.

 

[DRagor]

Never use cables from different model of PSU, as they are not necessarily compatible. If you were unlucky, you could fry motherboard this way. Damage to CPU cannot be excluded, but it is less likely.
Put your motherboard out of case, connect only 24-pin cable from PSU and maybe a case fan to motherboard, and try starting. If zero reaction, as PSU is known to work, means motherboard is dead.