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  Topic Review (Newest First)
10-18-2019 08:57 PM
Bold Eagle subbed for the content.............
10-18-2019 08:50 PM
rv8000
Quote: Originally Posted by The Stilt View Post
Quote: Originally Posted by rv8000 View Post
Thanks for the explanations.

Concerning the Scalar, at least by ASUS's definition, the only description they really offer within the bios is that altering the scalar level only allows the vcore/VID to sustain longer durations at it's defined level. They don't really mention anything about frequency, though in turn higher/longer sustained voltage does result in longer periods at a higher frequency. Would one have to increase the VID from auto to +10mV, in theory, to start to see higher frequency jumps even though the Auto OC is set to +200mhz? For instance: if I increased the VID value in the bios/PBO would I see larger than a 25mhz increase when to the best of my knowledge I'm not hitting any of the PBO limits?
Increasing the scalar only helps, if FIT causes a voltage limit that is below the "global Vmax" (LUVL), which is 1.5000V (unless manually set to a lower value, through the control introduced in AGESA 1.0.0.4).

This is rarely the case in ST workloads, but very common in MT scenarios, especially on 3700X and 3800X SKUs. That being said, I've seen it happening in ST scenarios as well.
For example, if you increase the PPT to say 128W, TDC to 100A and EDC to 140A you should see somewhat higher clocks and significantly higher voltages during e.g. Cinebench R20 MT test when you raise PBO scalar from 1x to e.g. 3x.
Thats because in MT scenario the voltage is limited by the stock reliability (FIT) and increasing the scalar (hence reducing the reliability) will allow the use of higher voltages.

Offsetting the voltages won't technically make any difference, since the CPU will follow its AVFS decisions when it operates in non-OC (i.e. manual) mode. Offsetting can get you around the PPT/TDC/EDC limits, but obviously it won't change what the CPU
expects and wants to receive, in terms of the voltage.

Let's say that you have a 3700X CPU with following V/F for Core 1: 4100MHz = 1.3250V, 4200MHz = 1.36250V, 4300MHz = 1.4125V, 4400MHz = 1.4625V.
When you increase the Fmax through Auto OC, the CPU will calculate the V/F for this range as well (most likely through extrapolation, similar to Intel). If it determines that the Core 1 will require
1.4750V for 4425MHz, 1.49375V for 4450MHz and 1.51250V for 4475MHz, then =< 4450MHz is the maximum you will see no matter what you do (due to 1.5000V hard LUVL / Vmax limit). You can offset the effective voltage, but not what the CPU needs and wants to see.

There is room for improvement in the way the AVFS currently behaves however, these improvements will not result in higher peak frequencies (only avg) even if they all would materialize.
There are two ways for the frequencies to improve on 3000-series CPUs: Either the Vmax (LUVL) is allowed to be increased (not going to happen frankly) or the manufacturing process improves from its current state.
AMD has themselves stated in their slides that the Fmax on 3000-series CPUs is being limited by the maximum voltage they can feed to the silicon.
Makes sense, though it’s rather hard to see why certain bios settings don’t work in practice when there is no concrete way to see all limitations.

I ran several cinebench tests with 2x, 4x, 6x, 8x, and 10x, and all resulted in the same peak VID reading of 1.438, and same peak vcore of 1.425v read in hwinfo. (Peak clock of 4425)

So while I understand what you’re saying, either something is being misreported, I’m being limited by something I can’t tangibly record, or something isn’t working properly.
10-18-2019 11:54 AM
Lupo91
Quote: Originally Posted by SeeGee View Post
Your results are better than mine to be honest. Can you run Atto Disk Benchmark and post your results? It has better granularity than CDM. I'll post my results when I get home and you'll see what I mean.




In my opinion the problem is in the bios of the motherboard, because it is not possible that both Nvme (Corsair MP 600/Aorus Gen 4) have poor performance in 4K
10-18-2019 11:44 AM
The Stilt
Quote: Originally Posted by rv8000 View Post
Thanks for the explanations.

Concerning the Scalar, at least by ASUS's definition, the only description they really offer within the bios is that altering the scalar level only allows the vcore/VID to sustain longer durations at it's defined level. They don't really mention anything about frequency, though in turn higher/longer sustained voltage does result in longer periods at a higher frequency. Would one have to increase the VID from auto to +10mV, in theory, to start to see higher frequency jumps even though the Auto OC is set to +200mhz? For instance: if I increased the VID value in the bios/PBO would I see larger than a 25mhz increase when to the best of my knowledge I'm not hitting any of the PBO limits?
Increasing the scalar only helps, if FIT causes a voltage limit that is below the "global Vmax" (LUVL), which is 1.5000V (unless manually set to a lower value, through the control introduced in AGESA 1.0.0.4).

This is rarely the case in ST workloads, but very common in MT scenarios, especially on 3700X and 3800X SKUs. That being said, I've seen it happening in ST scenarios as well.
For example, if you increase the PPT to say 128W, TDC to 100A and EDC to 140A you should see somewhat higher clocks and significantly higher voltages during e.g. Cinebench R20 MT test when you raise PBO scalar from 1x to e.g. 3x.
Thats because in MT scenario the voltage is limited by the stock reliability (FIT) and increasing the scalar (hence reducing the reliability) will allow the use of higher voltages.

Offsetting the voltages won't technically make any difference, since the CPU will follow its AVFS decisions when it operates in non-OC (i.e. manual) mode. Offsetting can get you around the PPT/TDC/EDC limits, but obviously it won't change what the CPU
expects and wants to receive, in terms of the voltage.

Let's say that you have a 3700X CPU with following V/F for Core 1: 4100MHz = 1.3250V, 4200MHz = 1.36250V, 4300MHz = 1.4125V, 4400MHz = 1.4625V.
When you increase the Fmax through Auto OC, the CPU will calculate the V/F for this range as well (most likely through extrapolation, similar to Intel). If it determines that the Core 1 will require
1.4750V for 4425MHz, 1.49375V for 4450MHz and 1.51250V for 4475MHz, then =< 4450MHz is the maximum you will see no matter what you do (due to 1.5000V hard LUVL / Vmax limit). You can offset the effective voltage, but not what the CPU needs and wants to see.

There is room for improvement in the way the AVFS currently behaves however, these improvements will not result in higher peak frequencies (only avg) even if they all would materialize.
There are two ways for the frequencies to improve on 3000-series CPUs: Either the Vmax (LUVL) is allowed to be increased (not going to happen frankly) or the manufacturing process improves from its current state.
AMD has themselves stated in their slides that the Fmax on 3000-series CPUs is being limited by the maximum voltage they can feed to the silicon.
10-18-2019 09:25 AM
rv8000
Quote: Originally Posted by The Stilt View Post
The thing is that you cannot tell if Vmax is being hit or not, since there is no "flag" to indicate that.
Same goes for FIT, but with FIT you can at least ensure that its not the limit (by using PBO Scalar).

Frankly I do not know what exactly causes the Vmax to be lower on certain cores, or in certain workloads, but I'd assume it has something to do with SIDD (leakage).

I'll see if I can find a way to provide more data on this and the general behavior.
Thanks for the explanations.

Concerning the Scalar, at least by ASUS's definition, the only description they really offer within the bios is that altering the scalar level only allows the vcore/VID to sustain longer durations at it's defined level. They don't really mention anything about frequency, though in turn higher/longer sustained voltage does result in longer periods at a higher frequency. Would one have to increase the VID from auto to +10mV, in theory, to start to see higher frequency jumps even though the Auto OC is set to +200mhz? For instance: if I increased the VID value in the bios/PBO would I see larger than a 25mhz increase when to the best of my knowledge I'm not hitting any of the PBO limits?
10-18-2019 09:12 AM
SpeedyIV
Quote: Originally Posted by Lupo91 View Post
I also have the Corsair MP-600 1Tb, performance is poor in 4K, and I don't understand why.

I also tried the Aorus Gen4 1Tb, but more or less the same

Both have poor performance in 4K
You might find this interesting to read.

https://www.reddit.com/r/Amd/comment...ie_gen_4_slow/
10-18-2019 08:56 AM
The Stilt
Quote: Originally Posted by rv8000 View Post
If Fmax, Vmax, PPT, TDC, and EDC are not being hit, and I'm sitting at 49-50c in single core bench's workloads why would a 3700X not boost higher or at least try to boost higher and crash?

With PBO Enabled and +200mhz set for Auto OC, PPT is set to 395w max, TDC and EDC are set 255a max, yet I peak at 4425mhz at 1.438v, ~65mV away from the Vmax limit AMD set for PBO while being miles away from the PPT, TDC and EDC limits. Sounds like something isn't working properly.

You mention Vmax can be lower for certain cores? What controls or dictates the limit? On-die hardware limitations? CPU side microcode limitations? Or is it a general thing within the AGESA code?
The thing is that you cannot tell if Vmax is being hit or not, since there is no "flag" to indicate that.
Same goes for FIT, but with FIT you can at least ensure that its not the limit (by using PBO Scalar).

Frankly I do not know what exactly causes the Vmax to be lower on certain cores, or in certain workloads, but I'd assume it has something to do with SIDD (leakage).

I'll see if I can find a way to provide more data on this and the general behavior.
10-18-2019 02:56 AM
zsoltmol
Quote: Originally Posted by The Stilt View Post
Quote: Originally Posted by rv8000 View Post
Obviously it's not as simple as this but:

Depending on the binning process you may get a 3800X that boosts to 4.5ghz @ 1.45v for single core loads.

Someone has a 3700X that boosts to 4.4ghz @ 1.4v for single core loads.

If PBO+Auto OC is based on microcode/software limitations at X value for TDP, amperage, temperature, voltage, etc... wouldn't an improved PBO algorithm theoretically let the 3700X boost higher when all of those criteria have not been exceeded? And in this specific situation AMD theoretically (and also in practice 65w vs 105w TDP) allowed the 3800X to hit a much higher PPT, TDC, and EDC, (enabling PBO and auto OC "should" allow for a higher PPT, TDC, and EDC than a stock 3800X).

I thought this was everyone's initial take away from Hallocks infamous video about PBO and Ryzen 3000, and why everyone was ticked off that it essentially did nothing. Seriously though, what's the point of having a +200mhz auto OC option for PBO and only getting 25mhz when I'm not hitting any of the 3 PBO limitations. Sure not every processor is the same but this sounds more like microcode/software limitation than hardware.



A direct quote from AMD stating it's a firmware limitation
No, it is simple as that.

Outside of PPT, TDC, EDC and the temperature (which generally are not an issue in ST workloads anyway), there are three different things which determine the maximum boost: Fmax (adjustable), FIT (adjustable) and Vmax (fixed ceil, floor provided in 1.0.0.4).

If Fmax (advertised max frequency + OC offset) is greater than your currently achieavable frequency, you are either limited by FIT or Vmax. If in this case increasing the PBO Scalar (aka FIT limit, aka reliability reduction) won't work, you are limited by Vmax (core specific V/F) and you are out of luck. A significant reduction in temperature is probably the only thing which would help at this point.

The Vmax limit is 1.5000V for all SKUs (at least for the current consumer line-up) and it is not adjustable. For some invidual cores or workloads it can be lower than that, but NEVER higher.
AGESA 1.0.0.4 will provide a control to lower the Vmax, but not to increase it (for obvious reasons). Lowering the Vmax will limit the maximum voltage requested by the cores to the set value during the peak boost, but obviously it will lower the achievable frequencies as well.
Really useful info!

What is the suggested SOC and Vmax voltage for 3900X? I use negativ offset for both now (-0.03750 for Vmax -0.02500 for SOC) and my CPU seems to boost higher in all situations. I let it to auto adjust Vmax with the negative offset so I dont use fixed voltages.

voltage ragnges according to HWinfo during various loads:
CPU 0.296-1.464
CPU during Cinebench R20 all core test: 1.288v

SOC 1.056-1.080v
SOC during Cinebench R20 all core test: 1.056v

PBO enabled with motherboard limits, scalar 1x, Auto OC MHz is +0 resulting 4600MHz max freq. Performance ENhancer is on Auto.

Cooling is not an issue in my case its well managed by a potent custom loop with 2 large radiators.
10-17-2019 07:08 PM
rv8000
Quote: Originally Posted by The Stilt View Post
No, it is simple as that.

Outside of PPT, TDC, EDC and the temperature (which generally are not an issue in ST workloads anyway), there are three different things which determine the maximum boost: Fmax (adjustable), FIT (adjustable) and Vmax (fixed ceil, floor provided in 1.0.0.4).

If Fmax (advertised max frequency + OC offset) is greater than your currently achieavable frequency, you are either limited by FIT or Vmax. If in this case increasing the PBO Scalar (aka FIT limit, aka reliability reduction) won't work, you are limited by Vmax (core specific V/F) and you are out of luck. A significant reduction in temperature is probably the only thing which would help at this point.

The Vmax limit is 1.5000V for all SKUs (at least for the current consumer line-up) and it is not adjustable. For some invidual cores or workloads it can be lower than that, but NEVER higher.
AGESA 1.0.0.4 will provide a control to lower the Vmax, but not to increase it (for obvious reasons). Lowering the Vmax will limit the maximum voltage requested by the cores to the set value during the peak boost, but obviously it will lower the achievable frequencies as well.
If Fmax, Vmax, PPT, TDC, and EDC are not being hit, and I'm sitting at 49-50c in single core bench's workloads why would a 3700X not boost higher or at least try to boost higher and crash?

With PBO Enabled and +200mhz set for Auto OC, PPT is set to 395w max, TDC and EDC are set 255a max, yet I peak at 4425mhz at 1.438v, ~65mV away from the Vmax limit AMD set for PBO while being miles away from the PPT, TDC and EDC limits. Sounds like something isn't working properly.

You mention Vmax can be lower for certain cores? What controls or dictates the limit? On-die hardware limitations? CPU side microcode limitations? Or is it a general thing within the AGESA code?
10-17-2019 04:20 PM
The Stilt
Quote: Originally Posted by rv8000 View Post
Obviously it's not as simple as this but:

Depending on the binning process you may get a 3800X that boosts to 4.5ghz @ 1.45v for single core loads.

Someone has a 3700X that boosts to 4.4ghz @ 1.4v for single core loads.

If PBO+Auto OC is based on microcode/software limitations at X value for TDP, amperage, temperature, voltage, etc... wouldn't an improved PBO algorithm theoretically let the 3700X boost higher when all of those criteria have not been exceeded? And in this specific situation AMD theoretically (and also in practice 65w vs 105w TDP) allowed the 3800X to hit a much higher PPT, TDC, and EDC, (enabling PBO and auto OC "should" allow for a higher PPT, TDC, and EDC than a stock 3800X).

I thought this was everyone's initial take away from Hallocks infamous video about PBO and Ryzen 3000, and why everyone was ticked off that it essentially did nothing. Seriously though, what's the point of having a +200mhz auto OC option for PBO and only getting 25mhz when I'm not hitting any of the 3 PBO limitations. Sure not every processor is the same but this sounds more like microcode/software limitation than hardware.



A direct quote from AMD stating it's a firmware limitation
No, it is simple as that.

Outside of PPT, TDC, EDC and the temperature (which generally are not an issue in ST workloads anyway), there are three different things which determine the maximum boost: Fmax (adjustable), FIT (adjustable) and Vmax (fixed ceil, floor provided in 1.0.0.4).

If Fmax (advertised max frequency + OC offset) is greater than your currently achieavable frequency, you are either limited by FIT or Vmax. If in this case increasing the PBO Scalar (aka FIT limit, aka reliability reduction) won't work, you are limited by Vmax (core specific V/F) and you are out of luck. A significant reduction in temperature is probably the only thing which would help at this point.

The Vmax limit is 1.5000V for all SKUs (at least for the current consumer line-up) and it is not adjustable. For some invidual cores or workloads it can be lower than that, but NEVER higher.
AGESA 1.0.0.4 will provide a control to lower the Vmax, but not to increase it (for obvious reasons). Lowering the Vmax will limit the maximum voltage requested by the cores to the set value during the peak boost, but obviously it will lower the achievable frequencies as well.
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