AMD PBO Bios Settings

killroy67

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So my friend and I both are curios as to what settings in the bios are required to enable PBO. I know of one setting for PBO under AMD/CBS/XFR Enhancement and the other under AMD Overclocking. As of now we have them set on Auto, but have read elsewhere that you have to set them both to Enable in order for PBO to work. So which setting is it Auto or Enable, and if its not Auto then why, what does Auto do?

I have tried both PBO settings on Enable and noticed no difference from Auto, but that may be because of my board and cooling. My freind on the other hand has a X570 Master with water cooling so maybe he would benefit from it more then I
 
I would love to understand why there are two separate, yet linked, PBO options in the first place. I guess one is put in by the MB vendor and the other is part of AGESA, but it's just a guess. Seems redundant to have both to me.
From my testing, you only need to set one of them to Auto or Enabled for Ryzen Master to show PBO as enabled with all of the boosted wattage and amperage values that go with it. For the C7H Wifi, it's 384W, 255A, 255A w/PBO enabled/auto on w/2700X.
 
I would love to understand why there are two separate, yet linked, PBO options in the first place. I guess one is put in by the MB vendor and the other is part of AGESA, but it's just a guess. Seems redundant to have both to me.
From my testing, you only need to set one of them to Auto or Enabled for Ryzen Master to show PBO as enabled with all of the boosted wattage and amperage values that go with it. For the C7H Wifi, it's 384W, 255A, 255A w/PBO enabled/auto on w/2700X.

It is convoluted ho they have it laid out, it would make more sense if the settings were under MIT. I have both my settings for PBO on Auto, which I always assumed was the same as Enable. I would like to find out if there is any difference between the two, if any at all.
 
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Nah one option is for gen 1 and plus chips.

Other option is used for gen 2.

That's why.

Use xfr for older gens.

Use CBS for 2nd gen.

Or the other way around.

Or use Ryzen Master and screw bios.
 
Nah one option is for gen 1 and plus chips.

Other option is used for gen 2.

That's why.

Use xfr for older gens.

Use CBS for 2nd gen.

Or the other way around.

Or use Ryzen Master and screw bios.


So do you mean disable the one under AMD Overclocking and Auto for the one under AMD CBS? Optimized bios defaults put both on Auto? Im all set with Ryzen Master, I find it to be very user unfriendly.
 
I wouldn't bother with PBO. Essentially, it's probably not going to do better than Precision Boost 2 which is what you get on "auto".
 
So do you mean disable the one under AMD Overclocking and Auto for the one under AMD CBS? Optimized bios defaults put both on Auto? Im all set with Ryzen Master, I find it to be very user unfriendly.

Let me boot up in a few mins and ill.look at mine and share what I'm using to help you out.
 
I wouldn't bother with PBO. Essentially, it's probably not going to do better than Precision Boost 2 which is what you get on "auto".

Isn’t it the same boost algorithm, just a different set of hard caps?
 
I wouldn't bother with PBO. Essentially, it's probably not going to do better than Precision Boost 2 which is what you get on "auto".

All the same I would like to get these two settings clarified, no one seems to really know for sure.
 
These are the two setting I have, one is under AMD CBS-XFR Enhancement and the other is under AMD Overclocking.

PBO XFR.jpg
PBO1.jpg
 
my Gigabyte X370 settings in the AMD Overclocking menu

Advanced
Motherboard
Auto
200MHz
Manual
0

Literally not much of a difference with it on or off if you are talking CB20 scores. I can boost to 4.4ghz though in games like bfv without an issue.
EDIT 4.4GHz
 
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my Gigabyte X370 settings in the AMD Overclocking menu

Advanced
Motherboard
Auto
200MHz
Manual
0

Literally not much of a difference with it on or off if you are talking CB20 scores. I can boost to 4.5ghz though in games like bfv without an issue.

Okay so this I can work with, now what is the difference from what your settings, and leaving it on Auto or Enable.

Also what does that setting under AMD CBS-Precision Boost Overdrive do, is that for older gen cpus?
 
PBO is not worth it. Its basically pushing processor higher but it really is depending on cooling, I mean you need very very good cooling. Disable PBO and let the processor use the stock PB2 and it will boost just fine. I actually got it to boost more that way.

PBO is Precision boost overdrive, enabling it just allows the processor to push more power through it.

PB2 is standard precision boost which is on by default if you have everything default, meaning no manual overclocking. It will even work with voltage offset if you choose to do some.
 
Okay so this I can work with, now what is the difference from what your settings, and leaving it on Auto or Enable.

Also what does that setting under AMD CBS-Precision Boost Overdrive do, is that for older gen cpus?

If i leave it as just enable it will boost to about 4.350 and core 1 and 2 will get to 4.450 GHz
If I disable it boosts to around the same. but core 1 and 2 will max at 4.350.
This is a 3800x and quick 5 mins plays in BFv at 1440p
I don't have that option under AMD CBS. Mine is just under AMD Overclocking.
 
PBO is not worth it. Its basically pushing processor higher but it really is depending on cooling, I mean you need very very good cooling. Disable PBO and let the processor use the stock PB2 and it will boost just fine. I actually got it to boost more that way.

PBO is Precision boost overdrive, enabling it just allows the processor to push more power through it.

PB2 is standard precision boost which is on by default if you have everything default, meaning no manual overclocking. It will even work with voltage offset if you choose to do some.

I agree in some respects. PBO is PB2 with extra power headroom etc... but it REALLY depends on cooling. A seriously good air cooler or custom water loop should net good results on PBO. But disable PBO and allow the chip to use pb2 naturally and you might find you like it more.
 
I find PBO does absolutely nothing on my setup. Not sure if it's a BIOS bug or not - But generally, the stock limits are no where near being 100% even with PBO disabled.
 
Ok use AMD overclocking. Not XFR. AMD oVerclocking is the new 3000 stuff. Only use that.

My 3900x with PBO hits 4.2 all core solid and 4.550ghz single.

Okay so XFR Enhancement I should disable?..........and AMD Overclocking- PBO leave on Auto or Enable. I notice also you can manually set the settings for this.

So just to see if I got this right:

AMD CBS PBO is the older PBO for 1st Gen Ryzen

AMD Overclocking PBO is PBO2 for the newer 3000 series
 
I agree in some respects. PBO is PB2 with extra power headroom etc... but it REALLY depends on cooling. A seriously good air cooler or custom water loop should net good results on PBO. But disable PBO and allow the chip to use pb2 naturally and you might find you like it more.

Im also asking for a friend who has a X570 Master and custom cooling, I think he may possibly benefit from PBO2 due to his setup.
 
Okay so XFR Enhancement I should disable?..........and AMD Overclocking- PBO leave on Auto or Enable. I notice also you can manually set the settings for this.

So just to see if I got this right:

AMD CBS PBO is the older PBO for 1st Gen Ryzen

AMD Overclocking PBO is PBO2 for the newer 3000 series

PBO has to be enabled. It allows for more power draw. But it may not necessarily benefit. Stock boosts are all covered with standard PB2 (Precision boost 2), which is default. PBO is basically pushing processor more but nothing guaranteed. For me it actually didn't do shit, I am on 360mm AIO lol.
 
PBO has to be enabled. It allows for more power draw. But it may not necessarily benefit. Stock boosts are all covered with standard PB2 (Precision boost 2), which is default. PBO is basically pushing processor more but nothing guaranteed. For me it actually didn't do shit, I am on 360mm AIO lol.

Which one is which though lol......I have AMD CBS XFR Enhancement PBO......and AMD Overclocking PBO. Both of these settings I currently have on Auto, I get the concept I just want to get the settings right.
 
Precision Boost Overdrive is NOT new for the Ryzen 3000 series. It's available on the 2nd generation Ryzen's as well along with Precision Boost 2. Nothing changed for Ryzen 3000 on that front. It's the same algorithm for both. What has changed is how you enable them in BIOS. PB2 and PBO are functionally the same thing. The difference is where they get their EDC, TDC, and PPT values from. PB2 uses the processor's defaults. PBO gets them from the motherboard or the user's input. The latter should be more aggressive, but what holds Ryzen back are not these values. This is why PBO essentially does nothing.
 
Precision Boost Overdrive is NOT new for the Ryzen 3000 series. It's available on the 2nd generation Ryzen's as well along with Precision Boost 2. Nothing changed for Ryzen 3000 on that front. It's the same algorithm for both. What has changed is how you enable them in BIOS. PB2 and PBO are functionally the same thing. The difference is where they get their EDC, TDC, and PPT values from. PB2 uses the processor's defaults. PBO gets them from the motherboard or the user's input. The latter should be more aggressive, but what holds Ryzen back are not these values. This is why PBO essentially does nothing.

So how do you properly enable PBO in the bios? There is a lot of good information in this thread, but I still cant nail down that one aspect of which are the correct settings to enable PBO.

Bios settings:

AMD CBS-XFR Enhancement- Precision Boost Overdrive.......Auto Disable Enable Manual

AMD Overclocking-Precision Boost Overdrive......Auto Disable Enable Advanced
 
Neither will do much of anything unless you force higher voltages which will quickly kill these 7nm chips. These things don't come near hitting the stock TDP/EDP/PPT power limits. What holds them back is the temp scaler. Neither option you list will do much of anything.

This isn't like the 2000 series that made decent gains just by unlocking the power limits with PBO.
 
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So how do you properly enable PBO in the bios? There is a lot of good information in this thread, but I still cant nail down that one aspect of which are the correct settings to enable PBO.

Bios settings:

AMD CBS-XFR Enhancement- Precision Boost Overdrive.......Auto Disable Enable Manual

AMD Overclocking-Precision Boost Overdrive......Auto Disable Enable Advanced

On an MSI, you just enable it in both places. You can also do manual + advanced and set the values, but as the poster above me states it isn't going to do anything. If anything, you may retard it's performance.
 
On an MSI, you just enable it in both places. You can also do manual + advanced and set the values, but as the poster above me states it isn't going to do anything. If anything, you may retard it's performance.

So putting them both on Auto or Enable is probably the best method.
 
So putting them both on Auto or Enable is probably the best method.

You actually have to put them both on enabled. Auto, leaves them in their default state, which is to use Precision Boost 2, not PBO.
 
Which one is which though lol......I have AMD CBS XFR Enhancement PBO......and AMD Overclocking PBO. Both of these settings I currently have on Auto, I get the concept I just want to get the settings right.

PBO is precision boost overdrive.
You actually have to put them both on enabled. Auto, leaves them in their default state, which is to use Precision Boost 2, not PBO.


This! I think lot of people confused precision boost 2 with precision boost overdrive.
 
So putting them both on Auto or Enable is probably the best method.

as Dan mentioned. Auto leave only precision boost 2 in play. Enabled allows the processor to consume more power and push beyond standard environment.
 
as Dan mentioned. Auto leave only precision boost 2 in play. Enabled allows the processor to consume more power and push beyond standard environment.

Which it will not do. The fact is, these CPU's are already pretty much at their edge anyway. What's limiting them isn't PPT, EDC or TDC values. That's all PBO changes.
 
Which it will not do. The fact is, these CPU's are already pretty much at their edge anyway. What's limiting them isn't PPT, EDC or TDC values. That's all PBO changes.

already said in my earlier post. PBO is pointless. Cheers.
 
Okay well all of these post are some great information and really help clear things up. I believe I finally have a much better understanding of how things work with these CPU’s. Thanks!!
 
So, does setting PBO to "Disabled" also disable PB2?
 
No. 'Auto' is disable per AMD. Disable is also disable. It's just a technical nomenclature type of thing that applies to PBO.

Really, unless you are doing manual overclocking, just leave everything in default settings with these CPU's, besides whatever you need to adjust for your memory.
 
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So, does setting PBO to "Disabled" also disable PB2?

No. It does not. Think of it this way, unless you set everything to manual and lock down a specific clock speed, PB2 is effectively always enabled. All PBO does is tell the CPU to override it's PPT, EDC and TDC values and get them from another source. In theory, it should allow the CPU to clock higher more often as the motherboard or user input PPT, EDC and TDC values are much more generous than the CPU's defaults. However, this is not what observe from these CPU's. Meaning, their is another limitation preventing the CPU's from going further with PBO enabled.

To further confuse you, in manual / advanced mode for PBO, there is an offset mode which allows you to raise the boost clock ceiling of the CPU by another 200MHz. Theoretically producing a 4.8GHz 12c/24t CPU using a 3900X as an example. Unfortunately, because other factors limit boost clocks, this doesn't actually happen either. I've never seen the offset add anything to the actual observed clock speeds of the CPU under any workload.

No. 'Auto' is disable per AMD. Disable is also disable. It's just a technical nomenclature type of thing that applies to PBO.

Really, unless you are doing manual overclocking, just leave everything in default settings with these CPU's, besides whatever you need to adjust for your memory.

The biggest problem is that the wording in the UEFI isn't very clear. The reason for this is that AMD told motherboard manufacturers that they had to have a menu for PBO that was essentially the same on all motherboards regardless of manufacturer. The motherboard manufacturers also kept the layout and menus they were using the same, so effectively, you get it in two places and though they impact one another to a degree, you have to set it in both places in order for things to work right. It's stupid, but AMD wanted to make sure that all the motherboard makers were on the same page when it came to tuning menus.
 
OK, it's making some more sense now. Thanks Dan and Mchart.
 
So Im aware that I have limitations with my cooling and motherboard VRM's, so enabling PBO will probably make no difference from where Im at currently. But if a person has a top line board like the Gigabyte Master or Extreme, combined with a excellent custom water cooling solution, in theory if they enable PBO in those two locations, they should be able to go beyond the 4600ghz of the 3900X up to 4800ghz?
 
So Im aware that I have limitations with my cooling and motherboard VRM's, so enabling PBO will probably make no difference from where Im at currently. But if a person has a top line board like the Gigabyte Master or Extreme, combined with a excellent custom water cooling solution, in theory if they enable PBO in those two locations, they should be able to go beyond the 4600ghz of the 3900X up to 4800ghz?

No, because even with a decent water cooling setup you'll still be stuck due to the way it scales clock with thermals as you won't be able to bring the temps down low enough. With how little total TDP these chips actually are capable of drawing and the thermal scaling limitations - You're wasting money on some expensive cooling setup if it's for anything more than just the looks of the setup.

There is literally no reason to mess around with overclocking these chips unless you want a specific value forced via manual overclocking, but if you do this you are sacrificing single core speeds...

PB2 is pushing these chips as far as they can safely go, and there is nothing you can do to modify the values that PB2 scales off of.

The only tweaking you can do that will net you real performance gains with a 3000 series build is just with memory.
 
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