Question Mobo will not post - Asus Prime z390-A

Dec 4, 2019
So i decided to upgrade my mobo and CPU.

My new build is

Asus Prime z390-A
i7 9700k
Corsair Vengeance LPX 3000mhz (2x8gb) RAM (QVL)
GTX 1080
700W PSU (gold rated)

Basically, when i power up the mobo starts to post and fails on the DRAM check. CPU led indicator comes on, then the DRAM which stays on for a few secondsvafter which it then restarts at cpu and repeats.

I get no video out. I have reset the CMOS, reseated the ram in single/dual and all the different slot arrangements and i get the exact same issue everytime

It also seems like the memok!_ii switch does nothing as there is no LED coming on to show its performing an action.

I'm really stumped here. Its the second baord ive tried as i got a replacement thinking it was broken. The all components are tested to be working from the previous build.

Any help would be greatly appreciated.


It's been stated in the past, 80+ efficiency ratings don't state the quality of the PSU. What is the make and model of the PSU and how old is it? Wattage also doesn't indicate how good a unit may or may not be.

Without the discrete GPU, breadboarded, are you able to get to BIOS and remain there indefinitely? Also, what were your previous motherboard and CPU?