Ryzen 9 3900x the undervolting champ?

Calavaro

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This 3900x I have has been very good, but I live in a hot country so temps are always a little bit higher.

Undervolting drops overall performance by ~23% in Cinebench R20, but very significantly reduces temperatures.

I underclock the CPU to 3GHz all core, and use 1.0125 vcore (actual 1.016v). Temps go from 92-93C under extended full load on stock, to 66C! Ambient is 31-34C. Package powerdraw comes down from 142W (max stock), to 90 Watts.
Idle is 40W and 48C, which is still high though.

This is really good for day to day running, and when actual rendering/gaming/streaming power is needed, it's only 3 clicks away in the Ryzen master software.

And now I don't have to buy an AIO right away.
 
Nice! I still run my Radeon fury undervolted too... Save a bit of wear and tear, heat and power. Although, the only speed I lost was I couldn't overclock as high.
 
How is this different from degrading the performance of any other CPU to lower the power consumption?
 
How is this different from degrading the performance of any other CPU to lower the power consumption?
You still maintain a buttload of performance even with a 23% degradation in performance. It is still faster than a 3700x in multithreaded programs. I could probably clock the CPU higher and be faster, but I was shooting for the lowest possible temps while still being quicker than a 3700x.
I'm not saying you can't undervolt or underclock any other CPU, but you might lose more than you gain (eg. performance drops below the next CPU tier). This is one of many many MANY reasons why manycore CPU's should have been mainstream a decade ago....
 
I don't see the point. In anything lightly threaded you sacrifice a lot of performance, and anything multithreaded you would want to run as fast as possible as that is the whole point. Otherwise just buy a 65 W CPU.
 
I don't see the point. In anything lightly threaded you sacrifice a lot of performance, and anything multithreaded you would want to run as fast as possible as that is the whole point. Otherwise just buy a 65 W CPU.

You do not see the point for yourself and that is fine. If Calavaro was concerned about single threaded performance, he already made it clear he could clock the CPU higher and it would be faster. It is a clear win for what he is trying to accomplish and that is the cool thing about computer and desktop computers specifically, there is no one way only to do it. (Unlike phones or for that matter, tablets and laptops.)

Edit: Oh and buying a 65 Watt TDP processor would still be slower than his 3900X and the way he decided to configure it.
 
You do not see the point for yourself and that is fine. If Calavaro was concerned about single threaded performance, he already made it clear he could clock the CPU higher and it would be faster. It is a clear win for what he is trying to accomplish and that is the cool thing about computer and desktop computers specifically, there is no one way only to do it. (Unlike phones or for that matter, tablets and laptops.)

Edit: Oh and buying a 65 Watt TDP processor would still be slower than his 3900X and the way he decided to configure it.
Buying an expensive multi core CPU to deprive it of a quarter of its performance doesn't make much sense any way you slice it.

Besides, he said:
"This is really good for day to day running, and when actual rendering/gaming/streaming power is needed, it's only 3 clicks away in the Ryzen master software."
If you run it full speed when you need to and otherwise it consumes little power anyway, what is the point at all?
 
Buying an expensive multi core CPU to deprive it of a quarter of its performance doesn't make much sense any way you slice it.

Besides, he said:
"This is really good for day to day running, and when actual rendering/gaming/streaming power is needed, it's only 3 clicks away in the Ryzen master software."
If you run it full speed when you need to and otherwise it consumes little power anyway, what is the point at all?

Whats the point in doing anything then? What is the point in overclocking or even building a computer, since you can just buy one off the shelf and it will just work? Basically, he has already said why and you clearly do not agree, that is the cool thing about building and configuring our own computers, we use them the way they work best for us. When he needs full performance, 3 clicks and he is done, and I think that is fantastic, because he is doing things the way he wants. This is the reason I do not like tablets or phones, it is their way or the highway.
 
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Buying an expensive multi core CPU to deprive it of a quarter of its performance doesn't make much sense any way you slice it.

Besides, he said:
"This is really good for day to day running, and when actual rendering/gaming/streaming power is needed, it's only 3 clicks away in the Ryzen master software."
If you run it full speed when you need to and otherwise it consumes little power anyway, what is the point at all?

Pretty much this. The CPU downclocks on it's own anyway - without having to mess about in Ryzen Master. Mine idles at 28C, and max I have seen (CineBench) is 77C. Granted I'm on a AIO, but again its a $500 processor - cool it properly.

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Buying an expensive multi core CPU to deprive it of a quarter of its performance doesn't make much sense any way you slice it.

Besides, he said:
"This is really good for day to day running, and when actual rendering/gaming/streaming power is needed, it's only 3 clicks away in the Ryzen master software."
If you run it full speed when you need to and otherwise it consumes little power anyway, what is the point at all?
Day to day, browsing and doing general tasks with some minor photoshopping my powerdraw, my temps, in my situation is much better.
I don't need 4.25 Ghz all core boost, or 4.525 Ghz singe core boost to save me a second of render time for small tasks and I don't see the need to load the CPU with 1.46vcore scrolling down a webpage... and I don't load the stock cooler as high. Lower temps and lower powerdraw benefits me a lot. I'm running ~12C (53F) lower idle and ~30C (86F) lower on load, day to day.
4 clear advantages for me.
1. Lower powerdraw from the wall (roughly 3 kWh saved per day).
2. Lower temps, which is always good for longevity of electronic eqiupment. I plan to keep this system for 5-7 years. I care what the system can do then, not that it is OP now.
3. Offers me enough power for what I do day to day while allowing me points 1 and 2.
4. If I need more power in the future, I just go to stock speeds, or overclock with a nice AIO later on.

Then you'll argue that the CPU lowers vcore and clockspeeds when not in use... not really. Looking at what AMD has explained they want to maximize your available power all the time, so the CPU throttles up in nanoseconds very high, even typing some text. AMD has set the powerdraw and available power to be very agressive for some reason, it never stays at low enough power and speed to offer any meaningful savings. Hard limiting the vcore and clockspeeds does offer some real powersaving and temperature advantages, while sacrificing speed I dont need posting on these forums.
 
Seems like buying a less powerful CPU to begin with is better for your use case. 23% is huge. Ryzen has what’s called clock stretching which means you can undervolt way down while maintaining “stability” but losing performance the entire time. Seems pretty pointless to buy a CPU and gimp it’s performance by 1/4 when you could’ve just saved the money with a cheaper cpu
 
Seems like buying a less powerful CPU to begin with is better for your use case. 23% is huge. Ryzen has what’s called clock stretching which means you can undervolt way down while maintaining “stability” but losing performance the entire time. Seems pretty pointless to buy a CPU and gimp it’s performance by 1/4 when you could’ve just saved the money with a cheaper cpu

I cannot say that I agree with this statement at all. Might as just be saying what I said earlier, just buy an off the shelf system because there would be no benefit to building your own, with the way you are thinking. Oh, and just how much performance do you need to browse these forums? Plus, 3 clicks later and it is there if he needs it which I find cool, no pun intended. :D :) We can all choose how to configure our own personal builds to suite of taste because, otherwise, just use a phone or tablet, and it would be their was or no way.
 
I cannot say that I agree with this statement at all. Might as just be saying what I said earlier, just buy an off the shelf system because there would be no benefit to building your own, with the way you are thinking. Oh, and just how much performance do you need to browse these forums? Plus, 3 clicks later and it is there if he needs it which I find cool, no pun intended. :D :) We can all choose how to configure our own personal builds to suite of taste because, otherwise, just use a phone or tablet, and it would be their was or no way.
Just because you tweak it, doesn't mean it makes sense.
 
Whats the point in doing anything then? What is the point in overclocking or even building a computer, since you can just buy one off the shelf and it will just work? Basically, he has already said why and you clearly do not agree, that is the cool thing about building and configuring our own computers, we use them they way they work best for us. When he needs full performance, 3 clicks and he is done, and I think that is fantastic, because he is doing things the way he wants. This is the reason I do not like tablets or phones, it is their way or the highway.

Exactly. I remember the days when personal computers used to be personal. Now personal computers are expected to serve corporate data-miners and the whims of internet forums.
 
Exactly. I remember the days when personal computers used to be personal. Now personal computers are expected to serve corporate data-miners and the whims of internet forums.
I have both undervolted and overvolted components currently in use. I just don't see much practical benefit in this case.
 
I cannot say that I agree with this statement at all. Might as just be saying what I said earlier, just buy an off the shelf system because there would be no benefit to building your own, with the way you are thinking. Oh, and just how much performance do you need to browse these forums? Plus, 3 clicks later and it is there if he needs it which I find cool, no pun intended. :D :) We can all choose how to configure our own personal builds to suite of taste because, otherwise, just use a phone or tablet, and it would be their was or no way.

It doesn't make any sense whether or not you agree. Why do something that the CPU does on it's own already, far faster and far more efficient than you could ever possibly do on your own? Yeah, the voltage and boost are broken on some early BIOS versions but that's a temporary issue. I have yet to hear of a use case for this that makes any sense at all. Do you have a reason that makes sense other than "because you can" since that's all you really said here?
 
It doesn't make any sense whether or not you agree. Why do something that the CPU does on it's own already, far faster and far more efficient than you could ever possibly do on your own? Yeah, the voltage and boost are broken on some early BIOS versions but that's a temporary issue. I have yet to hear of a use case for this that makes any sense at all. Do you have a reason that makes sense other than "because you can" since that's all you really said here?

Makes sense for the user that created this thread and he already specifically outlined why and what the end result is. The fact is, because you are not able to wrap your own personal use case around it does not make any difference, otherwise, as I said, just go out and buy a prebuilt machine, that would be good enough for you.
 
Makes sense for the user that created this thread and he already specifically outlined why and what the end result is. The fact is, because you are not able to wrap your own personal use case around it does not make any difference, otherwise, as I said, just go out and buy a prebuilt machine, that would be good enough for you.

No, he didn't. He said temps go down at full load, and the reason for that was reduced performance. If reduced performance is ok with you then a weaker CPU is the answer
If you're going to go into Ryzen master and change the settings each time you plan on running full load so you don't lose that 23% performance, there goes your cooler temps.

If you're pushing full load then you want full performance, if full load at 23% gimped performance is good for you, so will a CPU that's slower.

I'm all ears if you want another shot of making sense of it though.

This is one of the best examples of "just because you can doesn't mean you should"
 
No, he didn't. He said temps go down at full load, and the reason for that was reduced performance. If reduced performance is ok with you then a weaker CPU is the answer
If you're going to go into Ryzen master and change the settings each time you plan on running full load so you don't lose that 23% performance, there goes your cooler temps.

If you're pushing full load then you want full performance, if full load at 23% gimped performance is good for you, so will a CPU that's slower.

I'm all ears if you want another shot of making sense of it though.

This is one of the best examples of "just because you can doesn't mean you should"

Not going to convince you and not worth trying anymore. Thankfully, you are not the one that must serve for his use case, enjoy. :)
 
This 3900x I have has been very good, but I live in a hot country so temps are always a little bit higher.

Undervolting drops overall performance by ~23% in Cinebench R20, but very significantly reduces temperatures.

I underclock the CPU to 3GHz all core, and use 1.0125 vcore (actual 1.016v). Temps go from 92-93C under extended full load on stock, to 66C! Ambient is 31-34C. Package powerdraw comes down from 142W (max stock), to 90 Watts.
Idle is 40W and 48C, which is still high though.

This is really good for day to day running, and when actual rendering/gaming/streaming power is needed, it's only 3 clicks away in the Ryzen master software.

And now I don't have to buy an AIO right away.

You could always drop the Power Package Limit in BIOS and do not ever have to run Ryzen master ,might be easier.

Ex:Ryzen 3600X @ 546.7Mhz of adjust power for as fast as 3700X
 
No, he didn't. He said temps go down at full load, and the reason for that was reduced performance. If reduced performance is ok with you then a weaker CPU is the answer
If you're going to go into Ryzen master and change the settings each time you plan on running full load so you don't lose that 23% performance, there goes your cooler temps.

If you're pushing full load then you want full performance, if full load at 23% gimped performance is good for you, so will a CPU that's slower.

I'm all ears if you want another shot of making sense of it though.

This is one of the best examples of "just because you can doesn't mean you should"


It really feels to me like you and Meeho are missing the point. The point is that the reduced performance along with the reduced power draw and temps are great for his average needs. The stuff he does the most benefits from this. But he wants the power to be there when he needs it. It doesn't have to be instantly on-tap every minute of the day, he just re-enables the defaults in Ryzen Master (a trivial task) and it is all balls-out again when he needs it. Meanwhile the rest of the time, it is cool and sipping power. It makes perfect sense to me as I also leave my system on 24-7, often running background tasks that I need done, but not necessarily in a hurry. It's good to know the power is there when I really want it.

I think you are confused by the "full-load" testing he did as a comparison. I'm sure if he is REALLY planning on running a real "full load" workload he will kick the processor back up to defaults. It seemed to me to be a simple comparison to see exactly how much he lost in the new state from the default state. If he went to the lower spec CPU, that extra power would NEVER be there as an option.
 
I get all that. But that last paragraph is what the CPU does all on its own. When you don’t need the performance the clocks and voltage drop. When you do need it, it rises. It’s been that way for nearly 2 decades. The only thing he discovered is Ryzens clock stretching vs bluescreening when there’s not enough voltage.
 
I get all that. But that last paragraph is what the CPU does all on its own. When you don’t need the performance the clocks and voltage drop. When you do need it, it rises. It’s been that way for nearly 2 decades. The only thing he discovered is Ryzens clock stretching vs bluescreening when there’s not enough voltage.

It is SUPPOSED to work that way, but it ISN'T working that way yet. Excessive clocking and sitting at higher voltages at near-idle states without throttling back is an issue that a LOT of people are having with the Ryzen 3000 series chips. There are forum posts all over Overclockers.Net and the AMD Reddit about this - enough so that AMD is addressing these issues with explanations accompanied by Chipset drivers and AGESA updates. If it wasn't broken, they wouldn't be working so hard to fix it.

Ultimately, when the bugs get worked out, OP should not have to make this compromise. It SHOULD be automatic, and I believe that eventually it will be. But for now, this is an easy workaround.
 
It really feels to me like you and Meeho are missing the point. The point is that the reduced performance along with the reduced power draw and temps are great for his average needs. The stuff he does the most benefits from this. But he wants the power to be there when he needs it. It doesn't have to be instantly on-tap every minute of the day, he just re-enables the defaults in Ryzen Master (a trivial task) and it is all balls-out again when he needs it. Meanwhile the rest of the time, it is cool and sipping power. It makes perfect sense to me as I also leave my system on 24-7, often running background tasks that I need done, but not necessarily in a hurry. It's good to know the power is there when I really want it.
Full load is the only time undervolting brings tangible power benefits, so no, for daily usage he doesn't really benefit. Hence the confusion.
 
Full load is the only time undervolting brings tangible power benefits, so no, for daily usage he doesn't really benefit. Hence the confusion.

And yet OP is claiming tangible power benefits when not at full load. Both of your statements cannot simultaneously be true. Therefore, either his measurements are wrong or your assertion is wrong.
 
And yet OP is claiming tangible power benefits when not at full load. Both of your statements cannot simultaneously be true. Therefore, either his measurements are wrong or your assertion is wrong.
3 kWh difference per day seems impossible highly unlikely to me for regular daily usage, so I'm sceptical until further details.
 
Pretty much this. The CPU downclocks on it's own anyway - without having to mess about in Ryzen Master. Mine idles at 28C, and max I have seen (CineBench) is 77C. Granted I'm on a AIO, but again its a $500 processor - cool it properly.

View attachment 178488

Hi, these results look really promising. I am currently helping a friend tune their 3900x computer for performance. Could you talk about how you arrived at these scores, such as changes made in Ryzen Master (such as the use of the Ryzen Balanced Plan). I am guessing that you are not using any overclocking at all. Thank you.
 
Your CPU was never 90c.

AMD press released on line and released new chipset drivers.

Software couldn't read the chips thermal info correctly. In reality the chips are about deg cooler than reported. Use latest Ryzen Master for accurate reporting.
 
By limiting the max powerdraw by limiting max vcore (1.016v) and max speed (3Ghz). Yes, my PC is doing stuff 24/7. If it werent it would be a waste to keep it on 24.7, no? Best power saving is when you turn it off...

Your CPU was never 90c.

AMD press released on line and released new chipset drivers.

Software couldn't read the chips thermal info correctly. In reality the chips are about deg cooler than reported. Use latest Ryzen Master for accurate reporting.
I'm using the newest Ryzen Master 2.0.1.1233) with the "average" CPU temp. 92-93C under extended load while stock. Remember I live in a hot country. Ambient is rarely below 32C during the day and 27C during the night.
I'm also using the new beta drivers (1.17.29.115), and it does more agressively put cores to sleep, and doesn't ramp up cores quite as high under light loads.
For reference, both are found here: https://community.amd.com/community...te-5-let-s-talk-clocks-voltages-and-destiny-2)

Interesting to see that my results are disputed. I just said I got great results with good powersavings while keeping temps nice and cool by undervolting and underclocking. It doesn't impact anyone but me, and it works great for me. If you dislike that I'm happy with my results... well... o_O

You could always drop the Power Package Limit in BIOS and do not ever have to run Ryzen master ,might be easier.

Ex:Ryzen 3600X @ 546.7Mhz of adjust power for as fast as 3700X

When I need the power, I dont want to have to reboot and mess around with the BIOS. Takes too long. Ryzen Master lets me get all the power back, and more with literally 3 clicks. Thanks though.
 
Man dont get angry.

There was a technical flaw with temp reporting universally and also how apps ramped frequencies in the cores. Only way to fix it was with latest chipset drivers linked via official press release and you have to use Ryzen balanced power plan.

Undervolting was not the proper correction even if it worked.

I'm glad you found a method that works as a workaround for your climate but I live in Southeast US where we have regular 80+ humidity and temps on avg of 32-33c.

My temps dropped alot using latest agesa as well as the new chipset drivers and power plans.

But the official word from AMD was the chips, all chips, were being over reported as far as temps.

https://community.amd.com/servlet/J...2-124770/Community_Update5_Detailed_Brief.pdf
 
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By limiting the max powerdraw by limiting max vcore (1.016v) and max speed (3Ghz). Yes, my PC is doing stuff 24/7. If it werent it would be a waste to keep it on 24.7, no? Best power saving is when you turn it off...
And your PC is supposedly constantly using 125 W less on average due to undervolting. Sorry, but I have to press X on that one, especially since you stated the gain of only 52 W on full load.
 
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And your PC is supposedly constantly using 125 W less on average due to undervolting. Sorry, but I have to press X on that one, especially since you stated the gain of only 52 W on full load.
Crap. You're right. Its max 1.25 kWh saved per day. Not 3. Sorry, I messed up the calculation there. Dont know how I got 3kWh there... The rest is equally as valid though.
 
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Point me in the direction of a 12c with the ipc of zen2, 90w, 3GHz+ and same price or less....
 
Hi, these results look really promising. I am currently helping a friend tune their 3900x computer for performance. Could you talk about how you arrived at these scores, such as changes made in Ryzen Master (such as the use of the Ryzen Balanced Plan). I am guessing that you are not using any overclocking at all. Thank you.

Not using Ryzen Master at all. Bios set to full Auto for CPU, FCLK at 1800MHz, RAM at 3600Mhz CL14, PBO is OFF in bios. Ryzen Balanced Plan with a change to minimum processor power to 0% from 99%.
 
34C/93.2F ambient is dang hot!
I'm surprised how so many people missed this, undervolting would help a lot in this situation.
Although AMD is supposedly coming out with a 3900(non x) that would fit better for your use case probably. But it might not provide 3900x boost capabilities when desired. But maybe it will who knows....
 
I may have been a little overagressive with lowering the vcore.
Something decided to corrupt and kill my Bluetooth on the mainboard. No amount of trying to repair windows or drivers brought it back. Only a fresh install worked...

Or it might have been the system file corruption which have been talked about and which AMD is aware of. Not sure what may have caused it. I backed off any tweaking and run stock to see if the issue pops up again (now with a full system backup).
 
I may have been a little overagressive with lowering the vcore.
Something decided to corrupt and kill my Bluetooth on the mainboard. No amount of trying to repair windows or drivers brought it back. Only a fresh install worked...

Or it might have been the system file corruption which have been talked about and which AMD is aware of. Not sure what may have caused it. I backed off any tweaking and run stock to see if the issue pops up again (now with a full system backup).

That's some good info. I usually resort to a soldering iron, snips and a bad attitude when purging boards of bluetooth/wifi. Good to know when I get a Ryzen 3900X can do it with aggressive bios settings.
 
This 3900x I have has been very good, but I live in a hot country so temps are always a little bit higher.

Undervolting drops overall performance by ~23% in Cinebench R20, but very significantly reduces temperatures.

I underclock the CPU to 3GHz all core, and use 1.0125 vcore (actual 1.016v). Temps go from 92-93C under extended full load on stock, to 66C! Ambient is 31-34C. Package powerdraw comes down from 142W (max stock), to 90 Watts.
Idle is 40W and 48C, which is still high though.

This is really good for day to day running, and when actual rendering/gaming/streaming power is needed, it's only 3 clicks away in the Ryzen master software.

And now I don't have to buy an AIO right away.
So about a 23% drop in performance for a 29% drop in temperature (and probably power draw as well). If you are going for power/watt, it makes sense.
 
I have offset set to -0.1
Also did tests at -0.05

With my underpowered aio 240mm water cooled setup, I'm seeing 8-10% reduction in average and peak temps with better than stock performance in many tests and within 1% of the others

No instability.

I'll post the phoronix results when they fully finish tomorrow morning. But it looks like .1v is good for a free ~8C.

Aio still hits just under 80c in some cases
But stock was hitting thermal throttling in certain benchmarks.

Overall, I think I'll stick with the .1 uv. I'm seeing no downsides.


Asus load line is set to 3 for all load settings, cpu voltage frequency set to 400. Current limit set to 110% for all settings

edit:
https://openbenchmarking.org/result...1&obr_sor=y&obr_ab=y&obr_hgv=ryzen+3900x+uv.1

it's a bit of a mess when it comes to the sensors output because i had all selected my first couple runs and finally switched it to just logging the cpufreq and temp for the 0.1 uv run.

0.1uv seems totally safe. If you're seeing a performance drop, you're UV'ing wrong.
 
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