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Asrock Rack X470D4U VCore Adjustment

Hi guys, I’m trying to undervolt my Ryzen 9 3900x on an Asrock Rack X470D4U motherboard. Need to cram this into a 2u server with the Dynatron A24 heatsink and at default settings it looks like VCPU is showing 1.44 volts and the CPU is idling between 55-65c. I’ve looked around in BIOS and there are some parameters that I can adjust but it doesn’t look like I can set any negative values such as a -100mv offset etc. I’m a noob when it comes to over/underclocking so I am looking for some help in reducing the power draw on this CPU given the options in BIOS. Thanks!

There could be a so called Eco mode.

I implemented a server solution a little while ago with the same mother board and CPU in a 1u server and thermals were fine for me. Just had some really loud fans which is often the trade off you make for small form factor. If you are having problems with thermals I would recommend modifying airflow before trying to under volt it.

I contacted ASRock Rack and they gave me the following instructions:
“In BIOS setting – Advanced – AMD PBS – Clock Power Management, you can try change the setting to Enable. Or AMD CBS – CPU Common Options – Customer Pstates / Throttling, from there you may review some setting if that would let you ease off the idling CPU power”

I was able to change the pstate value from 48 to 46 which adjusted the core voltage down to 1.12. CPU is much cooler now.

Nice to know as I have the same board. I put a R7 2700 in though with a huge cooler so no issues for me. BUT…Good to know that thats avalible. Something more to play with as my home lab is never “done”…lol