# PBO2 Undervolt Help with 5800x



## Oasis (Jul 27, 2021)

Hi there

After watching this video ( 







 ) I might give it a try

I have a AMD Ryzen 7 5800x and I'm getting 72c max load on a NH-L12s (These temps I think are pretty good) (Small ITX PC) (Newest drivers/BIOS) (Stock settings)

Just some questions...

1. - If I go too far with the PBO2 Undervolt can I still open the BIOS?

2. - Which settings do I use?

3. - How do I test if it's stable?

Many thanks.


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## Mussels (Jul 27, 2021)

1. PBO cant crash your system, ever - with the exception of too much curve undervolting
2. see the link in my sig
3. again... with the exception of curve undervolting, they dont alter stability at all. since you get crashes at idle and load with the curve, you run some stress tests and then fart about on the PC. get a crash of any kind? reduce the negative offset.


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## Oasis (Jul 27, 2021)

Ok, thanks

Should I go up on 5 "steps" 5, 10, 15 etc then for the PBO2 Undervolt? (Max is 30 

And when it crashes will it crash to desktop or restart?


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## Mussels (Jul 27, 2021)

Oasis said:


> Ok, thanks
> 
> Should I go up on 5 "steps" 5, 10, 15 etc then for the PBO2 Undervolt? (Max is 30
> 
> And when it crashes will it crash to desktop or restart?


Word it that you go up for positive, down for negative
Most people find -10 to -15 is possible on all cores, otherwise you need to spend a lot of time finding what they do individually

as for crashes, that can vary. crashes arent exactly planned.. BSOD, restart, frozen black screen...


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## mtcn77 (Jul 27, 2021)

I think it is a good tool to control all your profiles simultaneously because there aren't any general settings to control each and everyone's threshold.
I think you can start with EDC, PPT first and then once you are settled on a TDP level for which your cpu cooler can keep up with - in respect to case internal ambient temperature - then curve optimisation is a good option.
PS-TL;DR:  don't push it if the temperatures haven't stabilised, or it will have inconsistent safe thresholds which will throw you off balance. TDP control via EDC helps at this point, the heat up phase levels faster and less rapidly.


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## Oasis (Jul 27, 2021)

Oh ok
Thanks
I meant "-5 etc" oops



Mussels said:


> Word it that you go up for positive, down for negative
> Most people find -10 to -15 is possible on all cores, otherwise you need to spend a lot of time finding what they do individually
> 
> as for crashes, that can vary. crashes arent exactly planned.. BSOD, restart, frozen black screen...


I did some testing with PBO2 undervolting (-15) but instead of getting the same temps or close with higher clock speeds (like the video) I got 10-15c more. 
Is there something I'm doing wrong?


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## Mussels (Jul 28, 2021)

Did you set a negative or positive offset? you get both choices


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## Oasis (Jul 28, 2021)

Mussels said:


> Did you set a negative or positive offset? you get both choices


I set it to negative offset


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## Zach_01 (Jul 28, 2021)

Oasis said:


> Oh ok
> Thanks
> I meant "-5 etc" oops
> 
> ...


Clocks were lower or higher than stock? What about PPT/TDC/EDC?


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## Oasis (Jul 28, 2021)

Zach_01 said:


> Clocks were lower or higher than stock? What about PPT/TDC/EDC?


100-150Mhz higher clocks, same power limits but it seems to be using more power


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## Mussels (Jul 28, 2021)

Oasis said:


> 100-150Mhz higher clocks, same power limits but it seems to be using more power


that means you were temperature limited previously


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## Oasis (Jul 28, 2021)

Mussels said:


> that means you were temperature limited previously


But I'm getting 10-15c higher  (from stock to PBO2 undervolt)


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## Mussels (Jul 28, 2021)

Oasis said:


> But I'm getting 10-15c higher  (from stock to PBO2 undervolt)


when you enable PBO to change the curve, you raise the limits off stock (therefore, no longer stock)
if you got higher temps and clocks, that fits with PBO boosting

you said you were at stock and your power consumption rose, so i replied to that


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## Oasis (Jul 28, 2021)

Mussels said:


> when you enable PBO to change the curve, you raise the limits off stock (therefore, no longer stock)
> if you got higher temps and clocks, that fits with PBO boosting
> 
> you said you were at stock and your power consumption rose, so i replied to that


Oh ok thanks

I'm just going to keep it at stock then for the most stable PC


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## Mussels (Jul 29, 2021)

Oasis said:


> Oh ok thanks
> 
> I'm just going to keep it at stock then for the most stable PC


If you follow the link in my sig and set the PBO settings there to limit the wattage with your undervolt curve, you'll get what you're looking for


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## gerardfraser (Jul 30, 2021)

Oasis said:


> Oh ok thanks
> 
> I'm just going to keep it at stock then for the most stable PC


Do not give up J/K .
Stock settings are perfectly fine on that AMD 5800X beast. Great PC Gaming CPU.Can not go wrong with taking advice from Mussels.

Here is my 5800X with AMD Curve Optimizer and if you like big numbers while PC Gaming, not that bigger numbers make any real difference but your e-peen will grow to legendary proportions 

EG: Shadow Of The Tomb Raider set to 5150Mhz in BIOS









BIOS setting ,I kept them simple for easy use. Everything is Auto in BIOS except for the changes shown. Now you need to test your own settings, these can get you started.


Spoiler











MSI motherboard here is how I set my Boost to 5150Mhz in the video above. 



Spoiler



You can set whatever you want and check stability. First off there are two different areas in all BIOS for PBO stuff.

In the AMD overclocking section ,go to PBO and set your AMD curve optimizer up- this will give you normal boost clock EG:5800X boost to 4850Mhz
In this section you can add up to 200Mhz it is the same for all motherboards EG: 4850Mhz+200Mhz=5050Mhz

If you want higher CPU boost clocks then you need to goto the second area for PBO settings
Advanced CPU Configuration set your PBO boost higher than 200Mhz like in the first section on MSI motherboards you can go as high as 500Mhz

To get 5150Mhz then set PBO here to 300Mhz
So 4850Mhz+300Mhz= 5150Mhz
save and test.


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## Mussels (Jul 31, 2021)

Heres what my 5800x was running at last night, seeing 4.4GHz all core boost, with the loop pre-heated from the GPU







You set the PBO settings to keep the temps controlled, and then the curve undervolt lets your clocks boost higher within that limit

I'm getting 4.4GHz all core and 5.05GHz single threaded boost (yes, its rare with modern games)... and the performance is freakin amazing, cause it still gets pretty close to 5GHz in gaming (i limit background tasks when gaming on this system)


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## Oasis (Jul 31, 2021)

Whats a good benchmark to test the performace of the CPU?
Is CPU-Z okay?


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## outpt (Aug 1, 2021)

CPU-Z cinebench20 or cinebench23. for stability core cycler


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## mtcn77 (Aug 1, 2021)

Oasis said:


> But I'm getting 10-15c higher  (from stock to PBO2 undervolt)


That is a sign you have started from way past the performance curve and going in the right direction. Don't just leave it at default. AMD has only recently started taking control from OEM's and issued their own profiles. You wouldn't know what the motherboard did at 'auto' only a microarchitecture ago.


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## Mussels (Aug 1, 2021)

Oasis said:


> Whats a good benchmark to test the performace of the CPU?
> Is CPU-Z okay?


Cinebench R23 with its 10 minute test is fantastic


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## Oasis (Aug 1, 2021)

outpt said:


> CPU-Z cinebench20 or cinebench23. for stability core cycler


Ok, Thanks



mtcn77 said:


> That is a sign you have started from way past the performance curve and going in the right direction. Don't just leave it at default. AMD has only recently started taking control from OEM's and issued their own profiles. You wouldn't know what the motherboard did at 'auto' only a microarchitecture ago.


Which settings should I use then?

This is my stock settings CPU-Z score https://valid.x86.fr/r3iq8e


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## tomfuegue (Oct 21, 2021)

PBO2 undervolting is awesome !. az:









						AMD Ryzen 7 5800X @ 4398.97 MHz - CPU-Z VALIDATOR
					

[e529be] Validated Dump by Anonymous (2021-10-21 01:43:26) - MB: Asus ROG CROSSHAIR VIII HERO (WI-FI) - RAM: 32768 MB




					valid.x86.fr


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## outpt (Oct 21, 2021)

It’s got more. My 5800x will do 4.700ghz all core without getting past 80C. Play with it some more.


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## tomfuegue (Oct 21, 2021)

outpt said:


> It’s got more. My 5800x will do 4.700ghz all core without getting past 80C. Play with it some more.


I'm looking for an extremely quiet computer, and with the 5800X without exceeding 54ºC passing the Cinebech R20 I think I'll be satisfied.


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## Bzuco (Oct 21, 2021)

@tomfuegue Can you please post what is the maximum CPU package power and voltage during cinebench test @4.4GHz ? Did you made tests for 4.2/4.0/3.8/3.6/... ghz and @maximum undervolt  ? If yes, please post. I made tests for my 11700F and want to really compare these two CPUs. It is hard to find undervolt tests on internet, because people simply do not care...


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## dont whant to set it"' (Oct 21, 2021)

@Bzuco Wait a "minute", I will have some for ya @44 multiplier and supplied with 1.175V , as I go out for a ciggy.
LE: see attached screenshoot of a cinebench r23 benchmark run at said settings.
Mine can run at lower than 1.175V, tough, for this one I ballparked it above just to be safe.


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## Mussels (Oct 21, 2021)

tomfuegue said:


> I'm looking for an extremely quiet computer, and with the 5800X without exceeding 54ºC passing the Cinebech R20 I think I'll be satisfied.


I too, like quiet computers.

But you do know these chips are perfectly safe at higher temps, and the fans dont need to be any louder?


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## outpt (Oct 22, 2021)

Run mine at default and it  isn’t loud.


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