This is free performance that I hadn’t taken advantage of in the year I’ve owned my Ryzen 5600, so I’m writing to this to advocate that nobody else wait as long as I did.

This is my guide. There are many like it, but this one is mine😁.

Curve Optimization is very easy - the testing being automated - and poses no danger whatsoever to one’s hardware; the worst you can expect is a Windows bluescreen, and that is no more deleterious than stalling a car. The only drawback is that you will need to have your computer running tests that render it useless – if you are prepared to leave it running overnight and/or while at work, though, this is not a problem – and it can take a long time.

1. Software (all free)

You will need:

• AMD Ryzen Master (latest version)

• HWINFO (to get the preferred core order and, optionally, compare before and after temps/power)

• Core Cycler (which contains PBO2Tuner – set and test curve optimizer values)

• CPU and gaming benchmarks (compare before and after performance, test for real-world stability)

2. Preliminaries

• Open HWINFO and uncheck both boxes, then navigate to “Central Processor(s)”-> <your CPU>. Make a note of the sequence after “Core Performance Order” – this is the order in which we will be testing them with Core Cycler, but you must SUBTRACT 1 from each value; Core Cycler starts numbering cores at 0, not 1.

• Open AMD Ryzen Master, select Advanced View, click Curve Optimizer, Per Core, then click Start Optimizing. Ryzen Master will then enter an automated procedure to generate its best estimate of what your CPU is capable of. Plan to be away from your computer for at least an hour while this is going on; when you come back, make a note of the values it generates, but DO NOT APPLY them - just close the program. Note that the “subtract 1” rule applies to Ryzen Master, as with HWINFO.

• Open the Core Cycler config file and make the following changes:

“stressTestProgram = YCRUNCHER”

“coreTestOrder = <your order from earlier>” - remember to subtract one from each

“numberOfThreads = 2”

“mode = 20-ZN3 ~ Yuzuki” in the ycruncher section, halfway down the page.

Some rationale:

The preferred core order is from WORST to BEST under-volter, and thus MOST to LEAST likely to fail – this is because the more preferred a core is, the more efficiently it is already running, and so the lower the voltage floor is. This makes testing faster because the most unstable cores will fail first, and dropped cores are left out of subsequent intra-session iterations by Core Cycler. Also, the ycruncher Yuzuki test is considered to be the most difficult one to pass, so we might as well start with it; you can – and should – run others afterwards.

• Open Windows Event Viewer, right-click on Custom Views, and click Create Custom View. Check “Warning”, and “Error”, then “By source”, and check “WHEA Error” in event sources. Name the view something meaningful, then exit the Event Viewer. This is just in case Windows ever BSODs – not likely, but possible – and we will need to know which core failed.

3. Testing – Round One

Create a spreadsheet like the one below – we will be keeping track of passes and fails.

When you’re ready to leave the computer alone, close all programs, open PBO2Tuner and key in the values given by Ryzen Master earlier, then click Apply, and minimize the program. These values are applied as though they were typed into the BIOS, and persist until they are changed, or the computer is restarted.

Run “Run CoreCycler” - the testing will begin, and will run until you stop it, or until every core has thrown an error.

~TESTING HAPPENS – LEAVE FOR AS LONG AS POSSIBLE, PREFERABLY 6+ HOURS~

When you come back to the computer, if Core Cycler is still running, stop it with Ctrl-C, and see which core/s, if any, have failed; Ryzen Master’s supplied values are usually rather optimistic, so you should expect some errors, which show up in bright purple text. (If you accidentally close the window, the log file contains all the same information, but is more annoying to parse.)

Scroll around the window and see how long it took for the core/s in question to error out – a fast error is anything under 10 mins, IMO, and a slow error is anything over. Any core with a fast error will be having its CO value increased by 2, while slows will have theirs increased by 1; if any cores don’t error (in which case, Core Cycler will still be running on those cores when you come to check), add them to the

“coresToIgnore =”

– no point hitting these cores again until Round 2.

(If the machine has reset, go into Event Viewer and look in your custom view – under Error, there will be an entry called “Processor APIC ID”, with a number, the number corresponding to a thread. Core 0 will run threads 0 and 1, Core 1, threads 2 and 3, and so on; whichever core was running the failed thread, increase its CO by 3 or 4 – that core was not even close to stable!)

Update your spreadsheet as shown below, with the adjusted CO values, and save it – when you are ready for your next test session, put these new values into PBO2Tuner before you start.

Keep repeating the above until all cores pass a session of this “all cores at once” testing.

and so on; my last all-core session, after shedding cores as they passed, looked like this:

4. Testing – Round 2

The next step is to extend the testing for each core. You can jump right to hitting one core for 6+ hours (as I did), or divide the cores into two groups (“front half, back half”, from the order earlier, is best), and test them one half at a time, Ignoring the cores in the other half. This will double the amount of time each core is under stress, and might generate errors that didn’t appear before, but you will be much closer to the true stable value thanks to the previous testing.

Change the core testing order to match the results from Round One - they might not be the same as the HWINFO values; for example, HWINFO gave me 2 ,1 ,0, 4, 3, 5, but ordering by the results of my Round One, worst to best, would be 0, 1, 4, 5, 3, 2.

Do the “increment on error” procedure from before, until the front half all pass, and then do the same for the rear half.

5. Testing – Round 3-4-5

If you like, you can split the cores again, and repeat, getting all groups stable. Keep splitting until you get to the point where only one core is being tested at a time:

• Ryzen 3 – four, two twos, four ones.

• Ryzen 5 – six, two threes (or three twos), six ones.

• Ryzen 7 – eight, two fours, four twos, eight ones.

• Ryzen 9 – 5900 = twelve, two sixes, then each six as per Ryzen 5; 5950 = sixteen, two eights, then each eight as Ryzen 7.

Yes, this CAN be a lot of testing, but Curve Optimizer CPUs are most likely to crash at the highest boosts (= lowest loads), so sheer duration is the only way to generate any confidence in stability. Thankfully, Ryzen Master gets us most of the way there; the values it gives are usually stable enough at least for idle Windows tasks.

My last round of Yuzuki was a 40-iteration test on each core individually - 5-6 hours per core:

From Ryzen Master's -28, -30, -30, -30, -30, -30, I ended up at -20, -21, -29, -26, -22, -26.

6. Further Testing

It is advisable to use the PRIME95 HUGE on each core in turn, as this is another very low load situation that lets the CPU boost to its maximum; make these changes in the Core Cycler config file. Feel free to try to some other presets as well – no such thing as too much testing. Read what other users found to be their “magic bullet” test settings, and try those out.

The best test, though, is, as always, to use the thing - browse, game, edit, do whatever you normally do.

7. Finalizing

When you’re happy that everything tests stably, go into the BIOS and enter your final values in the Curve Optimizer menu – this will save you having to use PBOTuner2 every time you boot up.

If your computer ever crashes (not impossible) use the Event Viewer to identify the rogue core, and increase its CO value in the BIOS.

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

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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