Question fit voltage?

MisterMeow

Reputable
Jan 29, 2016
144
6
4,715
13
I'm still new to PBO, I just came off a 2600 and I've been doing manual OC for the past few years so these new settings are slightly confusing.

I have a 3700x and an Asrock B450 Pro4 with the 1.0.0.4 AGESA patch B (most recent) BIOS update, the PBO settings on this motherboard have 5 limits in stead of the normal 3. The 2 extra limits are for SoC, however I just turn on XMP and use the dram calculator to set timings, it was perfectly stable with stock cpu settings. I don't know if I should be touching those SoC limiters in PBO or not. I also don't know if I should touch the scalar and auto OC settings either, I feel like auto OC gives me nothing, and scalar has something to do with voltages, so I'd rather leave that at x1.

As for fit voltage, I did what I read, which was to simply max out PBO limits and leave everything else at stock, run small fft's in prime95 and observe the SVI2 TFN sensor in HWinfo. I did that, and it mostly sat at 1.275v but would briefly jump up to 1.281 and sometimes as low as 1.22. What I don't understand is if I should pay attention to the most common reading of 1.275, or go with the very lowest of 1.22? And does that mean that's the number I type into the bios, or is that the number I aim for when accounting for vdroop?

And I'm well aware that an all-core OC on zen2 is a little redundant, I'm just trying to figure out as much as I can about zen2 and my chip. Any help is appreciated.
 
Last edited:
I'm still new to PBO, I just came off a 2600 and I've been doing manual OC for the past few years so these new settings are slightly confusing.

I have a 3700x and an Asrock B450 Pro4 with the 1.0.0.4 AGESA patch B (most recent) BIOS update, the PBO settings on this motherboard have 5 limits in stead of the normal 3. The 2 extra limits are for SoC, however I just turn on XMP and use the dram calculator to set timings, it was perfectly stable with stock cpu settings. I don't know if I should be touching those SoC limiters in PBO or not. I also don't know if I should touch the scalar and auto OC settings either, I feel like auto OC gives me nothing, and scalar has something to do with voltages, so I'd rather leave that at x1.

As for fit voltage, I did what I read, which was to simply max out PBO limits and leave everything else at stock, run small fft's in prime95 and observe the SVI2 TFN sensor in HWinfo. I did that, and it mostly sat at 1.275v but would briefly jump up to 1.281 and sometimes as low as 1.22. What I don't understand is if I should pay attention to the most common reading of 1.275, or go with the very lowest of 1.22? And does that mean that's the number I type into the bios, or is that the number I aim for when accounting for vdroop?

And I'm well aware that an all-core OC on zen2 is a little redundant, I'm just trying to figure out as much as I can about zen2 and my chip. Any help is appreciated.
Scalar you can leave on auto, I have never seen any benefits of it, it has an influence on time a core spends at peak frequency but that's measured in milliseconds. Once it reaches over the peak, load should shift to another core.
Your voltages seem more than good at full load, 1.3v+ (and me) is what most get.
 

MisterMeow

Reputable
Jan 29, 2016
144
6
4,715
13
Scalar you can leave on auto, I have never seen any benefits of it, it has an influence on time a core spends at peak frequency but that's measured in milliseconds. Once it reaches over the peak, load should shift to another core.
Your voltages seem more than good at full load, 1.3v+ (and me) is what most get.
Well when I run small fft's in prime95, I look at the HWinfo sensors. However those sensors conflict with HWMonitor. I've also seen readings in HWinfo that I know are flat out wrong, so I don't really know if the information I'm getting is reliable. And I also don't know if the max voltage I should type into the bios is 1.275 or 1.22.

When I manually OC'ed, I was hitting stable* all-cores of 4.3ghz at around 1.24-1.25v with vdroop bringing me down to 1.2-1.22 under load. I'm just not sure if this is within the safe tolerance based on the HWinfo sensors. I've seen others talk about how SOME cpu's can only handle as much as 1.25v safely. It's all slightly confusing just because of the amount of conflicting info on other forums.
 

Karadjgne

Titan
Ambassador
That's because Ryzens are still relatively new architecture, Intels haven't really changed much since Sandy-Bridge, just gotten smaller. People are still not dialed in as to the changes. Ryzen can handle upto 1.5v on idle or very low current use, 1.325v at a higher current use and closer to 1.2v at extreme current use. That still ends up around the same wattage overall, limited by pbo. OC kinda obliterates those limits, pbo not used, and what your definition of higher current use is, is different to others definition, so even 1.325v OC users are running into burnout conditions at extreme OC speeds, they simply demand too much current for the speed, and thats not what they are used to regulating, since it was never a regulation on their Intels, just set low/max current to max and go. A websurfer/light gamer having no issues at 1.325v and 4.4GHz, there's never any real load on the cpu to pull high current use, but that's different to a video editor or heavy gamer who'd burn out a cpu at the same settings.

Resulting in conflicting info from posters....

Ryzens work differently to Intels. Intels set max limits as working limits, you/cpu sets the speed and everything else has to just catch up as long as stability allows. So if you set 4.4GHz the cpu will pull its vcore, balanced against whatever current it needs for the wattage and you pray the VRM's are capable. In a nutshell Intel saying 'I'm gonna run this fast, you better cool me or else'

Ryzens work upto limits instead. You might set 4.4GHz, but you'll only get that if the cpu allows that. It's got set limits, like pbo, and works hard to get what you want, but isn't going to kill itself in the process. 'I'd like to run this fast, but can only do so if you have the cooling, otherwise I'll run as fast as I can safely'.

So changing pbo settings higher is generally not advised unless you have a motherboard that'll handle the extra wattage and cooling to deal with the extra wattage.

SoC is different. That's not specifically a pbo setting, it's a memory controller voltage setting. Because of variances in who makes what stick or sticks or models or speeds or timings, often the standard mc voltage isn't quite enough, 4 sticks needs more 'umph' in the mc to get it working, especially with higher speed ram.

If you think of high speed ram as a downhill slope, the higher the speed the steeper the slope, you'd not need any help running down the hill fast, but you'll definitely need a little bit better balance or you trip over your own feet. SoC can provide the balance, just that little bit extra. But you'd be talking in the 0.02v-0.05v bump range IF the mc needs it. Not to exceed 1.2v.
 
Reactions: CountMike

ASK THE COMMUNITY