Asus Crosshair VII Hero and new Ryzen 3000 (Zen 2) 7nm CPU's (D.O.C.P. troubles, fixed)

[Tikimotel]

Very  recently upgraded my PC.

I've bought a Asus Crosshair VII Hero (x470 based) motherboard and a R7 3700x.

With the Bios flash back option (with a USB stick rename bios to "C7H.cap" stick it in the root folder of the USB stick)

I've installed the (as of writing) latest bios version 2406. (Agesa 1.0.0.2)

 

When enabling D.O.C.P (a.k.a. XMP) the RAM voltages won't stick to DRAM Vboot voltages.

(this results in all GFX fans and NO POST, C15 post-code, just Clear CMOS button, and try again..)

It won't do POST because, at boot the voltages stay at JEDEC spec (1.2volts)

 

You have to edit "Dram VBoot Voltage" into the same settings as the DRAM voltages, my case "1.35", You will find the setting under extreme tweaker -> Digi+ Settings in "Advanced mode".

( 😉 Thanks, Google and Reddit)

Extra tip, set CPU voltage to manual and stick to 1.3-1.35Volts (the "Auto" 1.4++ is way too hot for "idle" and eventually performance)

 

 

 

 

 

[Mindovermaster Moderator]

Well, that's what kind of happens whenever you overclock, so...

[Tikimotel]

Enabling XMP or the AMD equivalent isn't exactly what most consider over clocking, BTW the new Ryzen chips support 3200Mhz.

[ReAnimation]

Thanks for the tip.

I've just switched from Intel -> AMD (first time using AMD in around 10 years) on the Crosshair VIII Hero.  I've noticed the CPU voltage bouncing around up to 1.5v so its not limited to x470 boards it seems.

 

Theres a thread running on reddit where a tech from AMD is explaining the behaviour of the Ryzen CPU's.  Apparently the voltage bouncing is expected due to the way the architecture boosts cores, apparently single core boost is fine to hit 1.5v, however the CPU should not 'stick' to 1.4+ volts when idle, which is what I have been experiencing.

 

There are lots of possible reasons for the behaviour (Multiple hardware monitors running at the same time, using Corsiar iCue), however no one is 100% sure.

 

I've currently set the CPU to 1.3 volts until things get clarified / more BIOS updates come out.

Edited July 20, 2019 by ReAnimation

[Tikimotel]

The CPU voltage is very odd, it seems the 3000 CPU's even boot with 1Volt, but they won't have any performance.

Steve from Gamers nexus did a video on the topic. Undervolting Ryzen 3000series