No power/boot; tests have been done, still no resolution

[felidaeblackwolfe]

Good morning,
So I'm working a new build for a friend and cannot get it to post or boot to BIOS. I have already tried the steps in the no post/no boot troubleshooting guide. I have also attempted to breadboard, but I'm thinking its a psu or MOBO issue.

When we attempted to boot to BIOS, we were able to get it to load one time. After this we have not been able to get anything to boot/post at all. If the psu is connected to the MOBO it lights up and shows it is receiving power, no MOBO light error, no beep error, no post beep. However, nothing else in the system is getting power (the PSU fan won't even turn on). When I disconnect the PSU and test it (both with a tester, and by shorting it) it has checked clean. Fan spins up, and connected case fan spins up. Reconnect to the MOBO, nothing. I have attempted removing all components but the necessities, one stick of RAM, even no RAM to try and get an error beep. Check the CPU no bent pins. Removed everything, tried testing it one component addition at a time. Nothing. When we booted to the BIOS the one time, it did read the CPU and the hard drives fine, but not the CPU fan. We shut down as it wasn't reading the USB at the time (test boot). I've had two other sets of eyes look at it as well, who have helped me with builds in the past, but they don't see any problem either.

So any ideas on if this is a bad MOBO, PSU, or what else I need to look at?

Components:
MOBO: Asus z370-e
PSU: Corsair 750w
CPU: Intel I7
CPU Cooler: Corsair H100i v2
Graphics: NVidia 1060
RAM: Ripjaw 8gb X2
SDD: 500g Samsung
HD: 2TB Seagete

 

[Gyustarr]

You need to check if the mobo supports the processor. Beyond the compatible socket many motherboards have a very limited range of compatible cpus.
You can also trying resetting the CMOS via jumper. Finally, if none of the above work you should check the psu for problems. Corsair has a reputation for faulty power supplies.