# PBO on Ryzen 3800X



## andy0x2a (Mar 6, 2020)

Hi experts.

I have heard lots of conflicting information about overclocking my Ryzen 3800X.
 Some people say to leave it at stock, and don't change anything. Most things I have read says don't manually overclock matisse, and to use PBO instead. Others say PBO can break things. 
I know PBO isn't supported under warranty, and is still technically risky, as it *can *break things, but it also sounds safer than manually overclocking per core. Especially with the amount of sensors and logic put in by AMD. 

Would you recommend turning on PBO, instead of leaving it at stock? 

Specs:

Ryzen 7 3800X
MSI x570-a-pro, latest bios update
Corsair H60 AIO
32GB Corsair 2666Mhz ram OC @ 3200Mhz
850W EVGA BQ
GTX 1660 Ti

it idles at 38/39, and under heavy load for 10 minutes reaches 85


----------



## TheLostSwede (Mar 6, 2020)

In my case, PBO doesn't really do much. Not sure why.
Long story short, what has given me the best performance increases since a week or so after launch has been to update to the latest UEFI, as this got my CPU up to the correct clock speeds over time.
It has also enabled me to overclock my RAM and tweak the timings to a level I'm very happy with.
A couple of guys here have had some very nice manual overclocks, I haven't bothered to be honest. I did play around with PBO before, but as I said, it didn't result in anything more than maybe a 50MHz boost at best.
Not sure your cooler is quite up to the task either, as the 3800X can get quite toasty with PBO enabled. You're clearly already hitting some fairly high temps under heavy load. Idle temperatures looks about right though.


----------



## andy0x2a (Mar 6, 2020)

TheLostSwede said:


> Not sure your cooler is quite up to the task either, as the 3800X can get quite toasty with PBO enabled. You're clearly already hitting some fairly high temps under heavy load. Idle temperatures looks about right though.



Thanks for the reply. I had replaced the stock wraith prism cooler with the corsair h60, it did seem to help a bit, but only a few degrees at idle and load. By heavy load, I mean a cpu stress test. When I run a cpu intensive game, I get CPU temperatures around the low 60s with KSP flying a 500 part rocket.

I am not sure if that makes a difference, as I probably won't be running a CPU stress test daily


----------



## mtcn77 (Mar 6, 2020)

TheLostSwede said:


> In my case, PBO doesn't really do much. Not sure why


You are the review guy, but let me state it is only there to curb high temperature resistance loss and current leak increase 'poole frenkel effect' on threadripper series.

Cpb and xfr can exploit your cpu's headroom quite sufficiently when you expect it to overclock. It is only deficient in following the near threshold voltage slope below boost levels.



andy0x2a said:


> I had replaced the stock wraith prism cooler with the corsair h60, it did seem to help a bit, but only a few degrees at idle and load.


I'd suggest you tighten the bolts, but the ring is '*not' *plastic, so that is a possibility. The ihs is dished, though.


----------



## andy0x2a (Mar 6, 2020)

mtcn77 said:


> I'd suggest you tighten the bolts, but the ring is '*not' *plastic, so that is a possibility. The ihs is dished, though.



 I will tighten the cooler's bolts, I had done it by hand, but I can give it a crank or 2 with a screwdriver.

I am not sure what you mean by the ring is not plastic. What possibility are you referring to? Also what do you mean that the IHS is dished? I understand that the IHS is the integrated heat spreader, and that the h60 is attached to it, but I am not sure what Dished means.


Thank you for your reply though.


----------



## TheLostSwede (Mar 6, 2020)

andy0x2a said:


> Thanks for the reply. I had replaced the stock wraith prism cooler with the corsair h60, it did seem to help a bit, but only a few degrees at idle and load. By heavy load, I mean a cpu stress test. When I run a cpu intensive game, I get CPU temperatures around the low 60s with KSP flying a 500 part rocket.
> 
> I am not sure if that makes a difference, as I probably won't be running a CPU stress test daily


Just wait until you fire up some more demanding games, it'll easily hit 70C+.
Nothing wrong with that, but a small liquid cooler is on par with a good air cooler, so don't expect your cooler to work any miracles. Even my cooler isn't amazing with these chips, as they get quite hot under extended periods of load. The custom loop guys are seeing 10 degrees cooler temperatures, if not more, but it's too rich for me.
Anyhow enjoy your new rig and don't worry about the OC part, the CPUs are fast enough once AMD and the board makers ironed out all the early issues. Just make sure it hits the advertised boost clocks.


----------



## mtcn77 (Mar 6, 2020)

andy0x2a said:


> I am not sure what you mean by the ring is not plastic.


Sorry for my mistake. I though it was an asetek made aio. Asetek's are round and have flimsy latches. A big YMMV.


----------



## andy0x2a (Mar 7, 2020)

mtcn77 said:


> I'd suggest you tighten the bolts





TheLostSwede said:


> You're clearly already hitting some fairly high temps



Thank you two for the advice. I tightened the bolts on the water cooler contact point, and I also added another fan for a push-pull configuration on the radiator. Dropped the stress test temperatur from 85 down to 77. Idles are now 35! 

@TheLostSwede do you think I have temperature room for PBO now?


----------



## eidairaman1 (Mar 7, 2020)

andy0x2a said:


> Thank you two for the advice. I tightened the bolts on the water cooler contact point, and I also added another fan for a push-pull configuration on the radiator. Dropped the stress test temperatur from 85 down to 77. Idles are now 35!
> 
> @TheLostSwede do you think I have temperature room for PBO now?



Keep your cpu, motherboard vrm/chipset and memory temperatures as low as possible.


----------



## MrGRiMv25 (Mar 7, 2020)

I think they tinkered a lot with 2rd gen (3000 series) Ryzen PBO, there's a decent link below on whats changed etc.


```
https://www.gamersnexus.net/guides/3491-explaining-precision-boost-overdrive-benchmarks-auto-oc
```

EDIT: changed Zen 3 to Zen 2 (3000 series)


----------



## the54thvoid (Mar 7, 2020)

andy0x2a said:


> Thank you two for the advice. I tightened the bolts on the water cooler contact point, and I also added another fan for a push-pull configuration on the radiator. Dropped the stress test temperatur from 85 down to 77. Idles are now 35!
> 
> @TheLostSwede do you think I have temperature room for PBO now?



My understanding (possibly read from the link in the post above) is that PBO does nothing to help create an OC. What it does is allow a more prolonged over-current (or higher voltage) to be used on the core to sustain an existing overclock. But that assumes temps, as discussed above, are kept in check. As @TheLostSwede has said, Ryzen benefits more from UEFI improvements for motherboard BIOS.


----------



## Zach_01 (Mar 7, 2020)

85C or even 77C is high enough temp. Unless you are sub-70C there is no point to use CPU other than with stock settings. What ever PBO can give these CPUs is mostly consumed by high temps like this. AMD did advertise potential boost over-drive but did not tell to users that they will have to bring down temps to like 50C for it to maximize overdrive.

There are more than one aspects affecting boosting with first the temp, second the current(A). Bring down temp and it will allow higher clock/voltage and current(A). Bring down current(A) with PBO settings and it will allow more clock/voltage and temp. Anyhow all the performance gains are from marginal and insignificant to some +3-4% at best while testing my little R5 3600. I expect higher binned SKUs to respond a little better than this but still I assume it would be nothing ground breaking.
Of course I can’t test it on 50C max as this would demand unconventional cooling solution, like a chiller.


----------



## eidairaman1 (Mar 7, 2020)

Zach_01 said:


> 85C or even 77C is high enough temp. Unless you are sub-70C there is no point to use CPU other than with stock settings. What ever PBO can give these CPUs is mostly consumed by high temps like this. AMD did advertise potential boost over-drive but did not tell to users that they will have to bring down temps to like 50C for it to maximize overdrive.
> 
> There are more than one aspects affecting boosting with first the temp, second the current(A). Bring down temp and it will allow higher clock/voltage and current(A). Bring down current(A) with PBO settings and it will allow more clock/voltage and temp. Anyhow all the performance gains are from marginal and insignificant to some +3-4% at best while testing my little R5 3600. I expect higher binned SKUs to respond a little better than this but still I assume it would be nothing ground breaking.
> Of course I can’t test it on 50C max as this would demand unconventional cooling solution, like a chiller.



Here's some ramblings from @buildzoidabout PBO










Some info on asus boards too


----------



## Deleted member 193596 (Jul 17, 2020)

i know i am quite late but i have a 3800x and i experimented with PBO for a month now.

230W/A 4x scalar works the best for me.


it doesn't work wonders but here is my result.


Stock: 4251 Mhz avg. across all cores in RB6 Siege after 1 match.
PBO: 4346 Mhz avg. across all cores in RB6 Siege after 1 match.

it does boost the average clock speed in normal load scenarios but does not have any influence on full all core loads.


----------



## moproblems99 (Jul 17, 2020)

andy0x2a said:


> Hi experts.
> 
> I have heard lots of conflicting information about overclocking my Ryzen 3800X.
> Some people say to leave it at stock, and don't change anything. Most things I have read says don't manually overclock matisse, and to use PBO instead. Others say PBO can break things.
> ...



You will get proponents of each way.  So try all three, at least pbo on and off to see which you like better.  If you go with PBO on, you will likely spend the next 3 months tweaking for 3-5% improvement.

Edit: Didn't realize this was necro'd.


----------



## CabanaBanana (Jul 19, 2020)

chiming in here, I just installed a 3700X with the wraith prism cooler and enabled PBO through asus uefi and I see slightly higher Cinebench R20 scores, both single and multi.

I am way too scared to play around with manually overclocking, so that is out for me. My basic understanding is PBO allows your chip more power. It won't actually raise your clocks but rather give it a chance to boost higher. It works directly with the motherboard and will basically "overdrive" the motherboards power limit to juice up your chip. Also I have noted that thermal headroom is pretty much a must when it comes to PBO which is why a lot of people don't see much of an improvement. So if you don't have good airflow or a good cooler, your chip will essentially tell it self "I cannot go much higher because I am getting too hot". Apparently the chip is very sensitive to heat.

I have a hard time understanding things but after watching GamersNexus talk about it for 40 minutes along with info from reddit, that is my basic understanding of PBO. Any one who is more informed on the topic, feel free to chime in and correct me, as I want to learn.

I have also read that the way these 3000 Series chips work, setting a static voltage (manual OC) even if its lower, can be harmful to the chip and degrade it faster. Which of course this pushes my fear of manual overclocking even more.


----------



## mtcn77 (Jul 19, 2020)

CabanaBanana said:


> chiming in here, I just installed a 3700X with the wraith prism cooler and enabled PBO through asus uefi and I see slightly higher Cinebench R20 scores, both single and multi.
> 
> I am way too scared to play around with manually overclocking, so that is out for me. My basic understanding is PBO allows your chip more power. It won't actually raise your clocks but rather give it a chance to boost higher. It works directly with the motherboard and will basically "overdrive" the motherboards power limit to juice up your chip. Also I have noted that thermal headroom is pretty much a must when it comes to PBO which is why a lot of people don't see much of an improvement. So if you don't have good airflow or a good cooler, your chip will essentially tell it self "I cannot go much higher because I am getting too hot". Apparently the chip is very sensitive to heat.
> 
> ...


Don't worry. The option does next to nothing on r7 series. It is for threadripper r9 to curb temperature gradient on power consumption. It basically doubles consumption unless you throttle with pbo by default. On r7, the option to decrease edc 10% less than ppt is found to work best.


----------

