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Need help Undervolting my 9900X

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Bond007 said:
But you don’t want to lower voltage with it?
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I can't see where else I would because that's the only spot where you can go in and make voltage adjustment's unless you mess with the curve.

What I'm trying to do is to get the core's to use as little voltage as possible and still run stable,then I was told I need to go into Curve Optimizer and adjust that and start off with a Negative 15 offset I was told I should be able to hit negative 15 and if I can't start at negative 10

From what I understand and have been told by a few people on other forum's and an AMD facebook group is that if you undervolt you will need to go in and use Curve Optimizer and I forget if that's so it get's more voltage as the core's ramp up and aren't starved for voltage or if it's that your taking away voltage there as well.

I think it's give some back when the core's ramp up because you've lowered the stock voltage and it isn't enough when ramping up and the voltage get's what it needs until it get's to the max boost speed then level's off to the lower voltage.

It's kind of like a carb on a car it get's enough fuel to idle and has enough to go 60mph but not enough move at lower speeds and it's starved at the lower speeds.

My problem is that anyone who knows how to undervolt the CPU I've talked to doesn't know jack about the X870E bios.
 
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Why wouldn't you just use a larger offset though, I don't think it's necessary to adjust the CPU voltage directly.

And yes, using the keyboard remains the best for setting BIOS things. Just because they give you mouse support, doesn't mean it's worth using :)
 
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JD said:
Why wouldn't you just use a larger offset though, I don't think it's necessary to adjust the CPU voltage directly.

And yes, using the keyboard remains the best for setting BIOS things. Just because they give you mouse support, doesn't mean it's worth using :)
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I'm just going by what others who have said they have done it this way,they it's the best way for whatever reason.

I know the one guy claimed using a larger Offset when he did his first undervolt didn't give him as good of temp's as the limiting the amount of max voltage the CPU can get under full load.

With the way one guy expalined it in a video that made sense to me is I've heard on Gamers Nexus and other video's about the silicon lottery and you either get a great CPU for overclocking or a terrible one,from what the guy said is that AMD for example say's with the 9900X it has a max boost of 5.6ghz per core so it needs to hit that so they make sure it hit's it by giving it in my case 1.35 volts but my CPU may run at 5.6ghz perfectly at 1.20 volt's per core which means less heat.

All the stuff I have seen they have said to adjust the voltage of the CPU first and go as low as you can until it won't run stable then go back up a bit in voltage then adjust Curve Optimizer and most say a -10 to -15 starting point is good and keeping adjust until unstable in stress test's and then go back to the last known stable setting.
 
wade7575 said:
I'm just going by what others who have said they have done it this way,they it's the best way for whatever reason.

I know the one guy claimed using a larger Offset when he did his first undervolt didn't give him as good of temp's as the limiting the amount of max voltage the CPU can get under full load.

With the way one guy expalined it in a video that made sense to me is I've heard on Gamers Nexus and other video's about the silicon lottery and you either get a great CPU for overclocking or a terrible one,from what the guy said is that AMD for example say's with the 9900X it has a max boost of 5.6ghz per core so it needs to hit that so they make sure it hit's it by giving it in my case 1.35 volts but my CPU may run at 5.6ghz perfectly at 1.20 volt's per core which means less heat.

All the stuff I have seen they have said to adjust the voltage of the CPU first and go as low as you can until it won't run stable then go back up a bit in voltage then adjust Curve Optimizer and most say a -10 to -15 starting point is good and keeping adjust until unstable in stress test's and then go back to the last known stable setting.
Click to expand...
I completely understand where you are coming from, and I have now watched a couple videos on exactly what you are trying to do.

Personally I disagree with that being the best method of optimizing for ryzen, and I feel it will take a lot of time and effort to achieve results that can be achieved in other ways more easily. I know we have chatted on the topic several times, but I feel like you could already have solid undervolting in-place and achieving your wants if using AMD's build in tools for optimizing instead of trying to manually adjust in this way.

You can fairly quickly use curve optimizer or the new curve shaper to undervolt and optimize the voltage curve (efficiency) for your specific silicon (per core, or all core if you are wanting to save time and just do a good enough undervolt). Agree with what you said in that -10 or -15 would likely be a solid starting point.

If you then want to further lower power consumption/heat (to get the results that you are trying to force in with manual voltage adjustment), you can either lower the max boost clock, lower the max temp, or lower the power envelope...pick whichever (or multiple) of those you have as your highest priority for what you are personally trying to optimize for. By doing any of those 3 things, you are simply adjusting the threshold limits for ryzen's built in clocking behavior, vice manually overriding it by setting specific voltage values.

To optimize ryzen you need to work with its excellent built in behaviors and adjust to your wants...not fight it with "old school" override techniques (obviously that is IMO, but I think the vast majority will agree).
 
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I know it's just 1 person's opinion on Reddit...

https://www.reddit.com/r/sffpc/comments/1evu8og/the_ryzen_9_9900x_is_so_efficient_actually_good

...but I would still say try the 105W ECO Mode. You might end up with similar results without all the hassle of stress testing. By manually limiting the CPU vCore, along with setting a negative curve, your really going to be pushing the lower limits and likely result in random crashes when you least expect.

Even in my case of not touching the vCore, and just using a negative core offset on my 5950X, I would get crashes when my PC was entirely idle and I had walked away from it. Absolutely annoying to come back to find everything you had open is now gone. What I'm getting at is you can't just stress test under high load, you also need to take into account all the low-power modes of the CPU too.
 
JD said:
I know it's just 1 person's opinion on Reddit...

https://www.reddit.com/r/sffpc/comments/1evu8og/the_ryzen_9_9900x_is_so_efficient_actually_good

...but I would still say try the 105W ECO Mode. You might end up with similar results without all the hassle of stress testing. By manually limiting the CPU vCore, along with setting a negative curve, your really going to be pushing the lower limits and likely result in random crashes when you least expect.

Even in my case of not touching the vCore, and just using a negative core offset on my 5950X, I would get crashes when my PC was entirely idle and I had walked away from it. Absolutely annoying to come back to find everything you had open is now gone. What I'm getting at is you can't just stress test under high load, you also need to take into account all the low-power modes of the CPU too.
Click to expand...
I had the same thing happen with my 5900x so I just pushed the voltage up slightly on the offset and it solved my problems, but I do agree since that is the whole point of eco mode it may be a much simpler way to get the results he is hoping for. I totally forgot about eco-mode on the 7000 and up chips
 
For me, I find out the maximum power the socket will allow the CPU to use with PBO with the heaviest workload that I know of. Once I do that, I use those as my power limits. From there I use the curve and boost override to tune my single and all core clocks.

For instance, I run my 5900X at 260/170/200 -24 all core, +200.

Curve shaper would be nice to have..

Edit again:

The CPU will do 260w PPT with like 265w package power.
 
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