Lowers voltage via negative offset u set, which lowers heat, which allows it to boost clock speed higher. How well a chip can run at below spec voltage varies with silicon. Too much negative offset and becomes unstable ultimately. Answer from Electrical-Bobcat435 on reddit.com
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Reddit
reddit.com › r/amd › my findings with the new curve optimizer with amd ryzen master
r/Amd on Reddit: My findings with the new curve optimizer with AMD Ryzen Master
April 17, 2022 -

So I have done about 9-12 hours extensive testings.

--

You WILL have to know your max PPT, TDC, EDC else this is just waste of time doing it and you will just be using default values which give you more aggressive under-volt than you might had opted before manually before using this.

Make sure to set those values in bios before moving on else you will just see default values in there no matter if you pick auto oc, or pbo, this was the case at least for me it would not pickup anything else than default values in software until manually set in bios.

So go to bios set values for those and set everything else on auto in PBO menu.


Verify and run a test just to verify settings are applied like on this screenshot, you don't have to run a full test if your settings where not added correct, go back and do it again.

My 5900X can handle these

PPT 185

TDC 125

EDC 170

Screen after completion..

https://i.imgur.com/otgetEQ.png

Video running test being stable for now and screen from HWiNFO just after finished tests.


Setup

5900X B0 Stepping early unit, not first week tho.

Asus x570-I ITX - Bios 4204 with AMD AM4 AGESA V2 PI 1.2.0.6b

3080 FE

16GB F4-3600C15-8GTZ

SF600

All in a loque ghost s1 case with some vector EK cooling setup on all parts.

All this was done by upgrading to latest bios, resetting bios to make sure no old values was stock and I only touched RAM timings with and dram voltage and PPT, TDC, EDC, PBO scalar x10, overclock 200mhz, rest was injected by ryzen masters into the bios settings after hitting apply.


Overall AMD have done a amazing job with this, even noobs can overclock and undervolt proper now 10/10 AMD clap clap

Do you wish to do it your self grab latest version here

https://www.amd.com/en/technologies/ryzen-master

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AMD
amd.com › content › dam › amd › en › documents › products › software-tools › faq-curve-optimizer.pdf pdf
FAQ - Curve Optimizer Feature in Ryzen Master What this feature is all about?
tune the AVFS curve of the entire CPU or specific cores of the CPU such that the tuning overrides the fixed curves that they are fused with, resulting in an ... Yes, both CPU and the internal graphics can be optimized. CPU can be optimized on ... Note: Automatic derivation of values is available for CPU only. For GFX, user has to manually set the values in the allowed range.
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Tom's Hardware Forum
forums.tomshardware.com › home › cpus
Question - Ryzen Master Curve Optimizer | Tom's Hardware Forum
September 6, 2024 - I haven't used Ryzen Master since ... to apply more voltage at a given clock speed, You can increase your all core boost by playing with curve optimizer as the CPU just wont need to dump a ton of voltage when it doesn't need to....
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Reddit
reddit.com › r/amd › guide: zen 3 overclocking using curve optimizer (pbo 2.0)
r/Amd on Reddit: Guide: Zen 3 Overclocking using Curve Optimizer (PBO 2.0)
December 22, 2020 -

UPDATE: I will continue to update this post with relevant learnings if I have them and updated results if I'm still tuning. I answered almost every question the first day, but I can't keep up with answering your questions, especially about your individual cases. Please help each other.


I come from many generations of Intel builds. Over the decades, the experience of overclocking Intel roughly translated to pouring voltage into core and maybe some into uncore while raising the multiplier until you hit a ceiling. Overclocking Zen 3 has been a completely different experience, with boost and PBO doing smart things that you want your OC efforts to support and optimize rather than replace.

I've spent many hours over the past four days overclocking both my 5900X and 5600X rigs, and I've learned a lot on the way. I figured I should share some important information with the community.

I included a background section for newbies that many of you might want to skip.

BACKGROUND

Your CPU will algorithmically boost the frequency of its cores depending on workload. For single threaded workloads, it will boost one core, and for multithreaded workloads, it will boost multiple cores. The frequency at which your core(s) will boost is governed by internal limits, such as power, current, voltage, temperature, and likely other factors, but the important thing to understand is that, holding limits constant, your CPU can boost one core to a higher frequency than it can boost multiple cores. This should make common sense to you.

PBO raises the current and power limits that govern your CPU's boost algorithm. You can raise your PBO settings as high as you'd like, but PBO has a hard limit of allowing 105W TDP CPUs to draw ~220W and 65W TDP CPUs to draw ~130W. PBO does not raise your CPU's max boost frequency, which is 4.8GHz stock for the 5900X and 4.65GHz stock for the 5600X, both of which are typically achievable only when the CPUs are boosting 1-2 cores. Practically speaking, enabling and maxing out PBO translates to your CPU boosting clocks during multithreaded workloads until your CPU is drawing ~220W / ~130W.

Auto OC raises the maximum stock boost clock by an offset, up to +200MHz, that you set. For example, a +200MHz offset will raise the stock 4.65GHz boost limit of a 5600X to 4.85GHz. Auto OC does not guarantee your CPU will be able to reach the boost clock under load. All it does is allow the CPU to try, but the CPU boosting algorithm will still take into account all the factors as usual to determine boost.

PBO 2.0 w/ Curve Optimizer: Undervolting is a way of overclocking CPUs and GPUs that have an internal table that maps voltage to operating frequency. Basically, a 50mV undervolt tells a CPU that instead of operating at, say, 2GHz at 1V, operate at 2GHz at 0.95V instead, and whatever frequency is mapped to 1V is now >2GHz. When a Zen 3 CPU is undervolted, this means that the same power limits that govern its boost algorithm all map to higher operating frequencies.

Curve optimizer basically allows you to undervolt each core independently.

GUIDE STARTS HERE

The steps for using Curve Optimizer to OC are:

  1. Curve Optimizer is part of PBO 2.0, so enable PBO and set it to your platform's limits.

  2. Under PBO, leave the scalar at Auto. Auto performed the best for me, but if you want to try to tweak this, I'll mention when you should do this.

  3. In Curve Optimizer, start with an all core undervolt of -5. Iterate between STABILITY TESTING (HIGHLY TRICKY. SEE BELOW.) and lowering this by -5 each time until you find the lowest stable value.

  4. Now you know the undervolt limit of at least one of your cores. You can now go into per core undervolting to find which cores you can bring down further using the same iterative method above.

  5. You're done. Now's the time to test a custom scalar value if you really wish to.

You will find that undervolting nets significant gains in both single and multithreaded performance. The more you can undervolt, the greater the gains.

AN IMPORTANT COMPLICATION: UNDERVOTING & AUTOOC

The relationship between undervolting stability and your AutoOC setting is critical. Broadly speaking, the more aggressive you undervolt, the more gains you get, but the higher you set your AutoOC offset, the less aggressive you can stably undervolt. This should make sense to you because your cores require more voltage to attempt the higher boost ceiling you specified. Practically speaking, you will likely find that your once stable undervolt setting is now unstable if you raise AutoOC from +0 to +200MHz.

Let's illustrate this relationship using an example. Say you set your AutoOC offset to +200MHz for a CPU with a 4.8GHz boost limit because you want it to boost to 5GHz. However, you find that the best stable undervolt you can achieve now results in a single core boost speed that barely blips to 4.95GHz. At this point, you should lower your AutoOC offset in order to undervolt further so that your undervolt boost can actually achieve what your offset specifies.

On the flip side, say you have a +0 offset, but your stable undervolt has your single core boost pretty much glued to its limit of 4.8GHz. In this situation, you should increase your AutoOC offset and back off on your undervolting until your offset is again equal to the what your undervolt boost can achieve.

EVEN MORE IMPORTANT: STABILITY TESTING

Your Curve Optimized undervolt will not be stable in low power workloads long before it will show any stability issues in any high power workloads, including every single benchmarking tool you use, including Cinebench and Prime95. An unstable undervolt will result in your PC sometimes randomly freezing, restarting, or BSODing when you're not doing much beyond browsing File Explorer or similar tasks.

Finding a low power workload for stability testing undervolting was the primary challenge of this entire process. The best one I found is the Windows 10 Automatic Repair and Diagnosis workload that can happen pre-boot. You can manually trigger this workload by restarting your PC after it posts but before Windows boots two consecutive times. The third boot will automatically start this workload after post.

This workload completing successfully means it will put you into a menu with a Restart option that you can click on to successfully restart your computer. An unstable undervolt can result in a myriad of different things going wrong, including:

  1. The PC suddenly reboots by itself before you reach the menu screen.

  2. A BSOD at any point in the workload.

  3. Making it to the menu and choosing to restart the PC, but then your PC freezes before restarting.

Once you have successfully triggered the Automatic Repair process, your next boot will be normal. However, if you reset your PC during this next normal boot before Windows successfully loads, it will trigger Automatic Repair in your subsequent boot again.

To test stability, I recommend 10x consecutive successful passes of this workload. This involves using the Automatic Repair workload to restart your computer, resetting your computer in the next boot to trigger the workload again, and repeating. I hope your PC has a reset button next to the power switch, because that comes in handy here.

UPDATE


This stability test works most consistently for finding the limits of your top 2-3 cores in terms of priority. You will notice that after finding these limits, you can undervolt your other cores significantly lower while still passing this test. I haven't yet found a reliable, consistent, and reproducible workload to test these other cores beyond just using your PC and waiting for a random restart or WHEA/other BSOD. Others have mentioned their own jury rigged tests in the comments that you can try.

Finally, low power stability testing is in addition to normal high load stability testing via the usual benchmarks. In fact, if you are failing those, then your OC efforts are in an even worse state than those who only fail low load stability.

MY RESULTS

My final results for my 5900X are:

Core 0: -18
Core 1: -5
Core 2: -18
Core 3: -18
Core 4: -18
Core 5: -18
Core 6: -18
Core 7: -18
Core 8: -18
Core 9: -18
Core 10: -18
Core 11: -18

Scalar: Auto
AutoOC offset: +25 MHz (4.95GHz stock boost limit for unknown reasons, so 4.975GHz with offset)

Cinebench R23 results: https://i.imgur.com/BQNcdbk.png

Takeaways:

  1. My all core undervolt wasn't stable beyond -5. As you can see, I eventually realized that it was my Core 1 bottlenecking that.

  2. My core 1 happens to be my highest priority core. This means my single threaded score is not nearly as impressive as I'd like. Silicon lottery at play here.

  3. I only really bothered individually optimizing Core 1, 2, 0, and 5, as those are my highest priority cores. I always tested cores 3 and 4 together and found stability with them at -20. I tested all my second CCD's cores (cores 6-11) in one batch; there may be some optimizations there, but I couldn't be bothered.

  4. While my highest priority core could only support a -5 undervolt, my other cores can be undervolted quite significantly, resulting in a pretty impressive multicore benchmark score, IMO.

My final results for my 5600X are:

Core 0: -8
Core 1: -8
Core 2: -4
Core 3: -8
Core 4: -8
Core 5: -4

Scalar: Auto
AutoOC offset: +200 MHz

Cinebench R23 results: https://i.imgur.com/88JXBOh.png

Takeaways:

  1. SC boost was glued to 4.85 GHz, which is the maximum allowed.

  2. More interestingly, MC all core boost was at 4.6-4.65 GHz, which is basically the stock single core boost of the chip. Pretty impressive.

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Reddit
reddit.com › r/amdhelp › do you use curve optimizer, curve shaper, or both ?
r/AMDHelp on Reddit: Do you use Curve Optimizer, Curve Shaper, or both ?
November 20, 2025 -

I'm running a 9800X3D on a X670-P motherboard, with latest bios.

So my question is about the Curve Optimizer and/or Curve Shaper options in the uefi.
I have been reading up on it a little, and watching some youtube vids, trying to get a handle on how it works. I do grasp, somewhat, how they both work singularly. But I'm still a bit unsure about if I should use them both together or choose one of them.

If you use them, how do you use them ?
Do you have them both enabled and configured, or do you use either or ?
In your experience, which config gives you the most out of your cpu ?
I know it will vary, from cpu to cpu and usecase, but I'm asking for your personal experience and settings/configuration.

Thanks in advance.
Your input is much appreciated.

Top answer
1 of 3
2
I'm using both... Started with CO, initially per core then gave up on that and started doing per CCD (I've a 9950x3d so 2 CCDs). This was my process: Decrease in -5 (or -10) steps, run AIDA64 stability test for 30 minutes, when you get instabilities go back to what you had before and leave overnight for 24h... With this I found I could do -20 on CCD0 and -30 on CCD1. Increase FB in 50MHz steps and re test for 24 hours, if you get a failure then decrease the offset, what I found was that I could stick with -20 and -30 up to 150MHz, then I got instabilities and so I had to decrease that by 5 each (tp -15 and -25) and the same for 200MHz (-10 and -20) Now, I'm running my Curve Shaper based on this, I've left CO at -10 and -20 and in CS I've applied: - AUTO for MIN (there is no real gain messing with min value and you can cause instability - ref - https://skatterbencher.com/2025/03/11/skatterbencher-85-ryzen-9-9950x3d-overclocked-to-5900-mhz/#comment-13750 ) - LOW for all temps -30 - MED for all temps -15 (tried with -30 but out was unstable) - HIGH for all temps -10 (tried -25 but it was unstable) - MAX for all temps 0 (tried -10 but windows wouldn't boot) Still tuning the CS portion but that's basically it! Once it's passed AIDA64 I'll do 6 hours of y-cruncher VT3 then 24 hours of Karhu or HCI memtest and lastly plan to leave it week running core cycler. Note that I've RAM OC'ed to 6400 and that has been throughly tested before I started PBO tuning. The process is painstakingly slow, tedious and time consuming... I probably wouldn't do it again unless I had a lot of time to kill. Hope this helps.
2 of 3
2
I have a maximized per core CO just because I found it fun, then I use curve shaper to add some voltage back at the minimum and low clock set points just to be sure it’s fully stable at lower clocks/idle. If you are just gaming on it, set it to -20 or -30 all core (you will need to do a couple stability tests to verify still stable, try aida64 extreme with fpu, cpu, cache selected, also Occt and y cruncher VT3 are good tests, try each for a few hours at least), and be done. Will help a little with temps/power and allow cpu to boost a little higher on all core loads.
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Linus Tech Tips
linustechtips.com › computer hardware › cpus, motherboards, and memory
Why do people say "curve optimizer" increase performance? - CPUs, Motherboards, and Memory - Linus Tech Tips
June 10, 2021 - When it really doesn't? For reference, I'm using a ryzen 5 5600X, I have PBO limits fine-tuned and auto overclock at +200Mhz. The CPU reaches 60 degrees in full load, 50~ in single core and boosts to 4.85GHz single core, 4.6 multicore stress testing Cinebench R23. I saw people on reddit praising ...
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AMD
amd.com › https://www.amd.com/en.html › documentation hub
Documentation for AMD Processors, Accelerators, and Graphics
December 16, 2025 - Find solution briefs, datasheets, tuning guides, programmer references, and more documentation for AMD processors, accelerators, graphics, and other products.
Find elsewhere
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Overclock.net
overclock.net › home › forums › amd › amd cpus
Ryzen 5000 series positive value for curve optimizer | Overclock.net
March 21, 2022 - Yes, it's perfectly safe - some people find their top one or two cores actually require a positive value in Curve Optimiser. Just remember, each step in the Curve represents either 3mV, 4mV, or 5mV (AMD has not been more specific).
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Linus Tech Tips
linustechtips.com › computer hardware › cpus, motherboards, and memory
Is Ryzen Curve Optimizer Per Core Just Not Worth It? - CPUs, Motherboards, and Memory - Linus Tech Tips
September 13, 2022 - Has anyone here actually tried to use the Per Core option for the Curve Optimizer to dial in precise undervolts for each core? Are there any tricks for judging stability or figuring out which cores to start tweaking? I had reduce my curve optimizer negative offset from 28 to 26 after two system c...
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Tom's Hardware
tomshardware.com › pc components › cpus
Curve Optimizer Heads To Ryzen Master For Zen 3 CPUs | Tom's Hardware
April 16, 2022 - Generally I only read the articles on Tom's Hardware and don't use the forums, but I have been an active user on overclock.net since 2005, if that counts for anything.yeah core cycler is a must for for CO testing, forget AMD curve optimizer (from what I see it returns crazy unstable values same with OCCT cycler I just completed 8h run pass for CO-17 for my 5900x.
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Reddit
reddit.com › r/amd › amd curve optimizer lower performance?
r/Amd on Reddit: AMD Curve optimizer lower performance?
December 30, 2022 -

I have an 5800x3d and an Asus x570-e gaming and using the curve optimizer now with negativ 25 and since i using this my CPU is boosting and 4.45 permanently and barly reach 75°C under gaming

But could this lowering my FPS because i noticed that my CPU is boosting some cores sometime only to 3.56 GHZ when others at 4.45GHz - is this normal under gaming or not?

Cinebench r23 it runs at 4300-4350 permanently with 4450 at the beginning

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Overclock.net
overclock.net › home › forums › amd › amd cpus
-=: AMD Ryzen Curve Optimizer Per Core + Curve Shaper + DDR5 OC :=- | Overclock.net
January 19, 2025 - Using Curve Shaper to adjust voltage and some eCLK info ... CO is per core, CS is all cores. CS allows you to adjust voltage for VFT, Voltage to stabilise Frequency for Temperature in use.
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H|ard|Forum
hardforum.com › [h]ard|ware › amd processors
Ryzen Master - PBO Curve Optimizer Control - Configure in Windows Now! | [H]ard|Forum
April 20, 2022 - I suspect the settings Ryzen Master spits out for CO use are a very good starting point. I wouldn't take them as 100% stable in all situations and definitely require more stability testing. However, it should shave off quite a few hours of testing if you were doing a proper job testing CO settings in the first place. ... Dialing in per-core curve optimizer settings can be tricky.
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HotHardware
hothardware.com › reviews › amd-power-curve-optimizer-guide-zen-3
Maximizing Ryzen 5000 Performance With AMD Curve Optimizer | HotHardware
Maximizing Ryzen 5000 Performance With AMD Curve Optimizer
Overclocking a CPU used to be a pretty simple process: change a bus speed or a multiplier, set an appropriate voltage, and voila: your Celeron 300A was running at 450 MHz, or your 600 MHz Duron was knocking on the 1 GHz barrier. These days with the advent of dynamic boost speeds and optimized frequency and voltage curves, processors intelligently ... AMD's new AGESA update adds simple controls for complex overclocking and under-volting that can bring nice performance gains.
Rating: 5 ​
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Thinglabs
thinglabs.io › how-to-use-the-amd-ryzen-curve-optimizer
How To Use The AMD Ryzen Curve Optimizer - thinglabs
September 8, 2024 - Curve Optimizer modifies the voltage and frequency curve, potentially leading to smoother frame rates in games. Users may experience less power draw and improved thermal performance, aiding in maintaining high-speed operation during gaming.
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Reddit
reddit.com › r/sffpc › ryzen curve optimizer
r/sffpc on Reddit: Ryzen curve optimizer
January 21, 2024 -

So first thanks to the few tips on the hardware choices, my terra build worked first time. 7900x, in eco mode, 32gb 6000mhz ram and a 6700x. All expertly built by my 9 year old, it was fun teaching about building computers.

I want to ask about this Ryzen tool that is supposed to automatically curve optimize. My system was stable in eco 105w mode, memory clocked at 6000mhz and the temps are cool - the heat sink cool to touch and ~40oC idle, all nice.

After the optimization finished I had to apply the settings it suggested -36. This made a bsod boot loop immediately after the sign in screen, kmode exception not handled. I had to clear CMOS to get back.

I confess even in my experience of 20+ years I've never really overclocked, I favor stability and don't like to push it if it's fast enough already. As I understand these curve optimizer settings aren't overclocking, but running at peak efficiency.

So what is the problem, the suggested settings are just way off? Do I even need curve optimization? I'm interested in cooler temps without changing the cooling solution and power efficiency.

I also read that we should have done curve optimization with a clear bios, I had eco mode (105w) and expo enabled in the bios?

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Reddit
reddit.com › r/overclocking › is curve optimizer the only setting to change when undervolting?
r/overclocking on Reddit: Is Curve Optimizer the only setting to change when undervolting?
January 7, 2026 -

New to undervolting. I currently have a 9800x3D on an MSI MAG B850 Motherboard. I changed my Curve Optimizer set to All Cores and lowered it to -20 for now. Will tweak according to feedback.

Temperatures are solid averaging 72-74°C (originally low to mid 80’s before undervolting) currently at 1.08 V, testing with AIDA64, but I’m wondering if there’s any other options I should change in the BIOS to fully make sure I’m not ruining my CPU.

If there are any other options I can change in MSI’s BIOS, please leave a reply!

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SkatterBencher
skatterbencher.com › home › amd curve optimizer
AMD Curve Optimizer - SkatterBencher
August 6, 2024 - And, actually, we can use the Fmax ... really missing out on about 300 MHz. Curve Optimizer is an incredible overclocking tool, especially if you have a CPU with lots of undervolt margin....
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Challix
challix.com › blogs › guides › how-to-use-the-amd-ryzen-curve-optimizer
What is the AMD Ryzen Curve Optimizer and How Do You Use It?
December 16, 2025 - Whether you’re a gamer, content ... its limits. ... When used carefully, the Curve Optimizer can improve performance and thermal efficiency without the risks associated with aggressive overclocking....