Z390 Extreme 4 Won't Power Up

Update: I and returning the MB and CPU for exchange. They were bundled and need to be returned together. Will follow up with closing statement if the new items solve the issue.

Hey just letting you know - you do NOT need both the 8pin and 4pin headers plugged in. If you have only the 8 pin (like me), it should still work.

I have the Z390 Extreme4 with a 750 Watt Corsair PSU using only the 8pin cpu header and it is working fine with my 9700k.

I'd look and make sure your Memory is in the right slot(s).

If you read the manual, it tells you to put them in specific slots if you're only using two sticks.

If you have something like 4 sticks of memory, try using two or just one and go from there.

Update: I just tested the PS with an old MB pulled from the case I'm using for the new system and the old MB powers up with all status lights on the PS green. So I think the PS is not the issue.

I think my issue is one of the following:

1) Insufficient/No power to CPU

2) Bad MB

RLGL I'm pretty sure the power supply is fine. I pulled it from my old system, it has indicator leds that show it's working, and the MB led's light up. I think it may have to do with power going to the CPU. I only had the 8-pin hooked up and it looks like maybe both the 8-pin and 4 pin need to be hooked up for an i5-9600K.

rsdaltx wrote: Hello All, I'm building a new machine around this Z390 Extreme 4 board. I believe I have everything set up correctly and it will not power up. System Configuration: Z390 Extreme 4 - BIOS Version 1.60 (stamp on MB) Intel Core I5-9600K (9th Gen) Noctura NH-U12S CPU cooler GSkill DDR4-2400 16GB (1 stick in A1 slot) CL15-15-15-35 Samsung 970 EVO NVME M.2 XFX Radeon RX580 ThermalTake ToughPower XT 775W Observations: The pins on the CPU socket do not appear to be damaged. I am using the 8-pin power supply with an 8-pin plug from the PSU. CPU cooling fan is plugged in to the CPU fan connector (# 3 on MB layout) with a 4-pin connector. After turning on power supply it's power LED is lit and MB LEDs are lit red. Pressing power button on case does nothing. Tried connecting both the power switch and reset switch from case to the MB power switch connections and nothing happens. Questions: Is this consistent with MB/CPU compatibility issues I've read about? Will this MB work with just 1 memory stick? Furthur Actions I'm Considering: Getting a cheap 8th Gen Celeron and using it to set and update BIOS Getting dual memory sticks to replace the single one. I should have done this to begin with. Returning the board and getting a different one.

Will this MB work with just 1 memory stick?

There is no memory of 16Gig. Single of that speed (2400) listed as single slot in the Qualified Vendors List (QVL).
https://www.asrock.com/mb/Intel/Z390%20Extreme4/index.asp#Memory