Question Can somebody provide a guide for a safe undervolt on a 5950x?

Noobpunk

Great
Jan 11, 2022
129
1
85
0
Hey all!

I have noticed through HWINFO that the CPU is running at an almost constant 1.488V at idle.

Does one need to go down the PBO route of undervolting? Or could I just set a negative value in the bios?

If somebody with experience please guide me to the right direction in regards to a safe undervolt, that would be greatly appreciated! I have no intentiont to overclock as well..It is just to reduce the temperatures!
 
I cant just adjust the VDDCR CPU Voltage Override in the bios?
You can, but there are problems with the two main options, fixed override and negative offset, that won't let you get very far. Most of this has to do with the fact that the CPU will still turbo boost to the maximum frequency under light loads. This maximum frequency becomes unattainable a lot sooner with lower voltages than with lower frequencies. That is, the relationship between voltage and frequency to get something stable is not linear.

PBO Curve Optimizer accounts for this. Advise you read over https://www.anandtech.com/show/16267/amd-precision-boost-overdrive-2-adaptive-undervolting-for-ryzen-5000-coming-soon
 

Noobpunk

Great
Jan 11, 2022
129
1
85
0
You can, but there are problems with the two main options, fixed override and negative offset, that won't let you get very far. Most of this has to do with the fact that the CPU will still turbo boost to the maximum frequency under light loads. This maximum frequency becomes unattainable a lot sooner with lower voltages than with lower frequencies. That is, the relationship between voltage and frequency to get something stable is not linear.

PBO Curve Optimizer accounts for this. Advise you read over https://www.anandtech.com/show/16267/amd-precision-boost-overdrive-2-adaptive-undervolting-for-ryzen-5000-coming-soon
Thank you for the response!

Is there a way I can undervolt doing this without overclocking the cpu?
 
Thank you for the response!

Is there a way I can undervolt doing this without overclocking the cpu?
When you enable PBO do not change the PPT, TDC or EDC entries and do not change the CPU Scalar entries. That means it's just 'enable' but not 'overclocking'. Also, do not change VCore or CPU Clock settings: leave them on AUTO.

Once you undervolt using Curve Optimizer it will probably improve performance some. That's because it's heating the CPU less, the boost algorithm sees the lower temps and can use a higher clock even at the lower voltage.
 

Noobpunk

Great
Jan 11, 2022
129
1
85
0
When you enable PBO do not change the PPT, TDC or EDC entries and do not change the CPU Scalar entries. That means it's just 'enable' but not 'overclocking'. Also, do not change VCore or CPU Clock settings: leave them on AUTO.

Once you undervolt using Curve Optimizer it will probably improve performance some. That's because it's heating the CPU less, the boost algorithm sees the lower temps and can use a higher clock even at the lower voltage.
I will try this if I need to undervolt! Thank you for this..
 

Noobpunk

Great
Jan 11, 2022
129
1
85
0
When you enable PBO do not change the PPT, TDC or EDC entries and do not change the CPU Scalar entries. That means it's just 'enable' but not 'overclocking'. Also, do not change VCore or CPU Clock settings: leave them on AUTO.

Once you undervolt using Curve Optimizer it will probably improve performance some. That's because it's heating the CPU less, the boost algorithm sees the lower temps and can use a higher clock even at the lower voltage.
What about if I also want to underclock a little bit? because on idle right now my cores are all almost maxed out.. https://ibb.co/wdnWLrM
 
What about if I also want to underclock a little bit? because on idle right now my cores are all almost maxed out.. https://ibb.co/wdnWLrM
If it's set up right it should boost and lower clocks dynamically, that's the way it works. It will boost a single core to a max clock to get even a small load completed quickly and then return it to a deep sleep state to rest and cool off. Then another core might get boosted for the next processing load. No cores will be be at a constant high clock speed unless you take the CPU multiplier off AUTO in the BIOS. One advantage of a lot of cores is for even light processing work there's always a 'rested' core available to boost so it's more likely to be able to boost to a high clock.

What monitoring program are you using? Many don't work right with Ryzen to show the boosting and idling of each core. Get HWInfo64 to see it properly.
 
Last edited:

Noobpunk

Great
Jan 11, 2022
129
1
85
0
If it's set up right it should boost and lower clocks dynamically, that's the way it works. It will boost a single core to a max clock to get even a small load completed quickly and then return it to a deep sleep state to rest and cool off. Then another core might get boosted for the next processing load. No cores will be be at a constant high clock speed unless you take the CPU multiplier off AUTO in the BIOS. One advantage of a lot of cores is for even light processing work there's always a 'rested' core available to boost so it's more likely to be able to boost to a high clock.

What monitoring program are you using? Many don't work right with Ryzen to show the boosting and idling of each core. Get HWInfo64 to see it properly.
I honestly have no idea how any of this works.

I have just noticed that in the edit power plan settings, my minimum processor state is at 100%. Could that also be a reason as to why in idle my cores are at this rate; https://ibb.co/wdnWLrM - If so can I reduce the rate because I would prefer my cores wouldnt be used up to this level at idle..

I am using HWINFO.
 
I honestly have no idea how any of this works.

I have just noticed that in the edit power plan settings, my minimum processor state is at 100%. Could that also be a reason as to why in idle my cores are at this rate; https://ibb.co/wdnWLrM - If so can I reduce the rate because I would prefer my cores wouldnt be used up to this level at idle..

I am using HWINFO.
Your core clocks average 3768Mhz. The maximum clock is 5048, the minimum is 2879. I'm not sure what makes you think it's at 'max clocks' all the time. It's spending a lot more time at 2879 than 5048.

Your cores aren't being "used up". Your processor is working fine and has a 20 year life ahead of it. But you'll get bored with it and want something else way before that.

I suggest you change to the Balanced power plan, that's all. Then open the Power and Sleep settings app (type it in cortana search). Select the preferred operating mode: Best Energy Savings, Better Performance or Best Performance. Don't mess with any of the settings in the power plan itself.
 

Noobpunk

Great
Jan 11, 2022
129
1
85
0
When you enable PBO do not change the PPT, TDC or EDC entries and do not change the CPU Scalar entries. That means it's just 'enable' but not 'overclocking'. Also, do not change VCore or CPU Clock settings: leave them on AUTO.

Once you undervolt using Curve Optimizer it will probably improve performance some. That's because it's heating the CPU less, the boost algorithm sees the lower temps and can use a higher clock even at the lower voltage.
Here are the settings that I will change as you stated;

View: https://imgur.com/a/43Kvbdg


Would this mean it is a safe undervolt?
 
Here are the settings that I will change as you stated;

View: https://imgur.com/a/43Kvbdg


Would this mean it is a safe undervolt?
So..that's setting all cores to a -12 curve. It would certainly be a "safe" in that it's not going to harm your CPU, but only if the undervolt is stable is it good. The way to find out is run some very light threaded work loads. One such is a Microsoft Defender virus scan. A better tool is CoreCycler because it hits all cores/threads with a light load to test them for stability. Check this article:

CoreCycler test tool for AMD Curve Optimizer released | KitGuru

Keep in mind it won't necessarily lower temperature since the boost algorithm is temperature seeking. But at a lower voltage it will be able to hit a higher clock, for longer, to get to the same temperature...so performance improves.
 
Last edited:

Noobpunk

Great
Jan 11, 2022
129
1
85
0
So..that's setting all cores to a -12 curve. It would certainly be a "safe" in that it's not going to harm your CPU, but only if the undervolt is stable is it good. The way to find out is run some very light threaded work loads. One such is a Microsoft Defender virus scan. A better tool is CoreCycler because it hits all cores/threads with a light load to test them for stability. Check this article:

CoreCycler test tool for AMD Curve Optimizer released | KitGuru

Keep in mind it won't necessarily lower temperature since the boost algorithm is temperature seeking. But at a lower voltage it will be able to hit a higher clock, for longer, to get to the same temperature...so performance improves.
What if I intend to undervolt with the aim of reducing temps? Because I am getting high 70s in Warzone with the 5950x
 
I was given the impression that if I undervolt the CPU this way I can reduce the amount of power that is being used thus reducing the amount of heat generated..
If the CPU boost algorithm isn't trying to push to a thermal target that may be true.

The purpose of undervolting with curve optimizer is to improve performance. It can improve it considerably if you have cooling capable of keeping temperature below the thermal target, which seems to be between 85 and 90C for R7's and R9's. If you're running in the 70's with curve optimizer you should be getting great performance.
 

Noobpunk

Great
Jan 11, 2022
129
1
85
0
If the CPU boost algorithm isn't trying to push to a thermal target that may be true.

The purpose of undervolting with curve optimizer is to improve performance. It can improve it considerably if you have cooling capable of keeping temperature below the thermal target, which seems to be between 85 and 90C for R7's and R9's. If you're running in the 70's with curve optimizer you should be getting great performance.
Ok! So I should set the CPU Boost to 0MHz just to make sure.

Thank you for the help! I will give this a try tomorrow.

Looking at Optimum Tech's video he only managed to get a negative offset of 12 for his 5950x so I will start at 10 for all and test through CoreCycle, if it is unstable then I will find reduce the offset for the ones that were unstable until theres no issue!
 

Noobpunk

Great
Jan 11, 2022
129
1
85
0
If the CPU boost algorithm isn't trying to push to a thermal target that may be true.

The purpose of undervolting with curve optimizer is to improve performance. It can improve it considerably if you have cooling capable of keeping temperature below the thermal target, which seems to be between 85 and 90C for R7's and R9's. If you're running in the 70's with curve optimizer you should be getting great performance.
EDIT* Sorry, do I have any other options in reducing temps for the CPU?
 

ASK THE COMMUNITY