ASRock Z390 - 8+4 CPU Power

[mjames33]

I've read a few threads on this topic but didn't get the specific answer I was looking for. I have a PSU (Corsair RM750x) with only a 4+4 EPS CPU power and my new ASRock Phantom 6 Z390 mobo has both the 8 and 4 ATX connector. I did read the manual which clearly states how to align a 4 pin in the 8 pin ATX Connector. However, it doesn't specify that the additional 4 pin connector is optional (Please connect an ATX 12V power supply to this connector.)

Clearly with an i5-9600k, the 8 pin can carry plenty. I did boot and everything seems fine at default clock. However, based on the ambiguity of the docs, it would be great if someone could confirm that the 4 pin is optional and only for extreme overclocking (or maybe SLI which I don't plan to do) or if there is reason to be concerned. I hadn't planned to upgrade the PSU but will if there is any benefit here.

 

[Dark Lord of Tech]

With the 9600k , the 8 pin will be plenty of power , with the 9900k , I would want to have both plugged in. 4 pin is usually for extra power when highly OC.

 

[geofelt]

Since you are now running OK, it demonstrates that the 4 pin is, indeed optional.
aux 4/8 pin is used to deliver extra power for overclocking and for extra power for populated pcie slots.

Your psu is an excellent one and can power any single modern graphics card.

Should, for any reason, you find yourself needing the 4 pin connector, you can use a 4 pin molex adapter.