3900x performing weird - Vcore

[Organized]

Hi guys,

 

I finally built my new rig with an 3900x on an ASUS ROG Strix X570-E Gaming with newest bios (released on 12th august 2019).

 

No PBO, just plain stock on the CPU side with DOCP enabled 3600MHz CL17 (4x8GB).

 

Default Vcore is around 1.45 to almost 1.5v (in idle) which is pretty stupid (I think?). In this setting, I'm getting ~6930 points in Cinebench R20. When I set offset to -0.1V I get ~7060 points. Temperature is no problem in both cases, max. 68°C during the benchmark, I'm using a Kraken X62.

 

When I set a manual voltage in BIOS, e.g. to 1.3V, Ryzen Master is still showing Vcore over 1.4V like in the default settings. Is my manual Vcore being ignored here or is Ryzen Master just too crappy?

 

See ya

[Zando_]

IIRC at stock the Ryzen 3000 series pulls up to 1.5v, that's normal (is a yikes coming from a 1.38v max safe on Zen + or most Intel chips though). Pulling that at idle is funky though, IIRC there's a whole thread somewhere on here devoted to sorting out voltage issues and such, I'll try and track that down. For now the first fix to test is making sure you're running the latest chipset drivers from AMD, along with Windows 10 1903, that includes a scheduler update and such so the CPU isn't as wacky (lots of monitoring software and the way older versions of W10 treat cores makes them boost all the time, even when they should be idling or something like that). 

EDIT: Here's the thread: 

 

[GrockleTD]

I remember hearing that part of the issue is that software is also reporting the last known voltage in instances where some of the cores get shut off

[Organized]

@Zando Bob Thanks, I will read into this.

@GrockleTD That's why I'm using Ryzen Master

 

It's getting more and more weird.

Vcore set to manual 1.30V -> under Load (CB R20) the Vcore drops to ~1,16V, only scored 6527 points

Vcore set to manual 1.35V -> under Load (CB R20) the Vcore drops to ~1,05V, only scored 5737 points

 

I don't get it.

[GoldenLag]

check with ryzen master for voltage monitoring. 

 

providing its running stock. then it runs as it should. 

 

 

people have allways had a voltage concern since 1st gen, but its just how the boost works. 

[Zando_]

18 minutes ago, Organized said:

It's getting more and more weird.

Vcore set to manual 1.30V -> under Load (CB R20) the Vcore drops to ~1,16V, only scored 6527 points

Vcore set to manual 1.35V -> under Load (CB R20) the Vcore drops to ~1,05V, only scored 5737 points

 

I don't get it.

Well this: 

16 minutes ago, GoldenLag said:

people have allways had a voltage concern since 1st gen, but its just how the boost works. 

And CPUs never behave like the BIOS says they should. I feed my 5820K 1.31-1.32v or so in the BIOS (for a 4.5Ghz all core OC), it pulls up to 1.34 under some loads. Sometimes they pull under what you gave them, sometimes over. I don't have LLC settings (Load Line Calibration, as far as I can tell from my experience and reading it's more or less how aggressively it pulls voltage on top of what you already gave it) on my board, you may on yours so you could take a look at that and see what it's set to. I do know Ryzens are quite picky, their boost is very finely tuned (even more so on the 3000 series, AMD really pushed them to the limit at stock, the boost is very clever), which makes them funky sometimes. My 2700X was picky, depending on temps, voltages, load, LLC, it'd boost to all sorts of speeds and pull different voltages whenever it felt like it. If giving yours a -.1v offset makes it perform better and there's no instability, and your temps are fine, I'd stick with that. AFAIK them pulling 1.45-1.5v is still in spec so it shouldn't cook itself (whereas if I gave my i7 that voltage it'd be a recipe for a very quick disaster). 

[Organized]

Well, I'm now using the following options:

 

PBO enabled, PPT 200, TDC 130, EDC 200 - no AutoOC

Vcore offset -0.1V

LLC is all on auto/default.

 

This is giving me ~7160 points in Cinebench R20. I'm okay with that