# Undervolting + Overclocking and Base/Boost frequency read out.



## agent_x007 (Jun 16, 2018)

Hello

So, I'm playing around with my GTX 1080 Founders Edition, and to make it more stable in Core Clock department I went ahead and modified Frequency/Vcore curve to better suit my needs.
I incresed max. frequency at 0.981V to 2012MHz, increased TDP and temp limits to 120%/92C and lastly I changed fan profile.
Screenshot of above settings running Superposition with Afterburner and GPU-z :



My question is this :
Why GPU-z says base/boost frequencies are only six or seven MHz higher than stock in this case, while Afterburner's "dial" clearly shows 1750MHz+ on base, and 2GHz on Boost ?
Is this a bug, or simply bad read ?

Thank you.


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## Vya Domus (Jun 16, 2018)

When you overclock by using the voltage/frequency curve you try to enforce a certain frequency independetly for each voltage point then software like GPU-Z or whatnot read out what frequency is set at that stock voltage point (which will likely by higher by a few Mhz). The reason why I say "try" is because the curve will still be tightly controlled by the driver and it will not follow 100% the desired curve. If you would have simply increased the core clock instead of messing with the curve that would have translated in a fixed offset for *all * voltage steps. (But as I said that doesn't really happen)

In addition to that , Nvidia cards do not really have a fixed "boost clock" figure , it's all dynamic. So the clock reported as being "Boost" is just what Nvidia figured would be typical at a certain voltage step but it's severely inaccurate under typical loads.

So , to wrap it up what GPU-Z and other software report as Default/Boost clocks is essentially irrelevant/inaccurate as the card will never run at those clocks precisely.





See , same thing in my case. I also have a custom curve.


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## agent_x007 (Jun 16, 2018)

Q1 : Why Afterburner's arrows for base/boost frequency show more than GPU-z then ?
You are claiming they read the same thing (ie. curve), and shoudn't be accurate :



Q2 : "Stock" voltage point for my card is 1,05V, and it is set at 2012MHz (just like every other freq./voltage point past 0.981V).

In my case, max. boost is 2012MHz.
At ~68C, GPU Clock gets droped to 1999,5MHz.
At ~76C it get's dropped again to 1987MHz, then drops to 1974MHz at ~82C.
Max. temp I reach is 86C, which represents 1966MHz GPU clock.
Frequency drop is VERY slow on this setting (which I wanted to achieve), unless TDP gets exceeded.


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## Vya Domus (Jun 16, 2018)

agent_x007 said:


> Q1 : Why Afterburner's arrows for base/boost frequency on dial show more than GPU-z then ?



It doesn't , from what I see the arrow is just below 2000 Mhz (likely 1987 as shown by Afterburner) just like in the real time tab in GPU-Z and in the game from what I see. I am not sure which clock reading you are referring to.



agent_x007 said:


> Q2 : "Stock" voltage point for my card is 1,05V, and it is set at 2012MHz (just like every other voltage point past 0.981V).
> 
> In my case, max. boost is 2012MHz.
> At ~68C, GPU Clock gets droped to 1999,5MHz.
> ...



Seems like it's functioning the way it's supposed to. Remember what I said , the card will not follow precisely the curve you want to impose , it will merely take a hint from it so to speak.


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## agent_x007 (Jun 16, 2018)

Stock and OC'ed dials, side by side :



Basic question : Why those move that much, while GPU-z reading stays almost still ?
On stock setting, white arrow represents 1607MHz, and red one 1734MHz (in-line with GPU-z reading).
GPU frequency at the moment, is represented by white bar.
With stock curve, Max. frequency at 1,05V is 1860MHz, and next drop step is 1,043V/1847MHz (seen above).



Vya Domus said:


> Seems like it's functioning the way it's supposed to. Remember what I said , the card will not follow precisely the curve you want to impose , it will merely take a hint from it so to speak.


I know, but I think it's more than simple hint.
If TDP and GPU Temps are low enough, curve is 100% accurate to what you should see.
When GPU heats up, that's the point at which GPU clock speed (and/or Vcore), will get dropped per every increase in temperature.
I wanted frequency/voltage/temp/TDP equilibrium, to be as close to max. frequency value as possible (it should give me best FPS stability, since GPU clock isn't all over the place because of temp/TDP throttling).


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## Vya Domus (Jun 16, 2018)

Afterburner must simply be reading different voltage steps than GPU-Z once overclocked. All you should care about is the real time clock.


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## agent_x007 (Jun 16, 2018)

I agree.
But when someone sees GPU-z screen with only +7MHz on base/boost, he might think card is almost not overcloked at all (while in reality, GPU is basicly OC'ed by over 150MHz).

What's the point of showing base/boost at all, when they don't represent what is set ?
I hope W1zzard can fix this...

Maybe GPU-z simply doesn't read freq/Vgpu curve which Afterburner modified ?
But then, why they moved at all if it was the case... weird.


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## Vya Domus (Jun 16, 2018)

agent_x007 said:


> What's the point of showing base boost when they don't represent at all what is set ?



Because that was always a feature worth noting about a GPU. The problem is that GPUs used to have fixed clocks and now they don't , but they still sort of need to report some figures in one way or another. GPU-Z and other software reports this as best as they can even though really they are irelevant.


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