Question Undervolting Ryzen CPU question.

[TYPICALHUMAN]

Hello. Is it safe to apply settings listed below in UEFI to undervolt a CPU? What do they result in? What does "curve optimizer attitude value" is responsible for? Lowers TDP by 25W? I'd like to set custom value of TDP but my UEFI does not seem to allow it. I can set "Eco mode" which sets 65W TDP, what Am I supposed to do If I want to set 95W? My CPU stock value is 105W (according to manufacturer). I need to lower temps.

Precision boost overdrive --> Advanced
PBO Limits --> Disabled
Curve Optimizer --> All Cores
All core optimizer sign --> Negative
All core curve optimizer magnitude --> 25

 

[Nighthawk117]

I'll leave someone else to answer as I'm only familiar with this on Intel. Out of curiosity though can I ask what CPU you are using?

 

[hotaru.hino]

Hello. Is it safe to apply settings listed below in UEFI to undervolt a CPU?

If by "safe" you mean no damage to the hardware, there's no real possibility of that happening. If by "safe" you mean the system will be fine and stable... that depends if the CPU is stable enough at those values.

Run a single threaded test to ensure the CPU is stable. Undervolting mostly affects the boost clock ceiling, which the CPU only gets to in a single thread workload.

What do they result in?

Generally speaking, CPU that consumes less power, outputs less heat, and can boost harder or longer because how hard a CPU can boost generally is affected by thermals.

What does "curve optimizer attitude value" is responsible for?

It correlates to what voltage to use for what frequency. In video card tweaking, this is the V-F curve. Only AMD hides a bunch of those details so you're not actually modifying that curve directly.

Lowers TDP by 25W? I'd like to set custom value of TDP but my UEFI does not seem to allow it. I can set "Eco mode" which sets 65W TDP, what Am I supposed to do If I want to set 95W?

There's probably another setting buried in your motherboard's UEFI that allows you to set a PPT value. Keep in mind for 105W TDP CPUs, the default PPT value is around 125W.

My CPU stock value is 105W (according to manufacturer). I need to lower temps.

This can help lower temps, but ultimately how hot the CPU gets is still dependent on your cooling setup.

 

[TYPICALHUMAN]

I'll leave someone else to answer as I'm only familiar with this on Intel. Out of curiosity though can I ask what CPU you are using?

Ryzen 7 5800x.

 

[Nighthawk117]

Ryzen 7 5800x.

I thought it was, just thought I'd ask. I undervolt my CPU but it's Intel so never used curve optimiser.

Can I also ask what cooler you use, I ask because I have a Ryzen system that runs quite hot.

 

[TYPICALHUMAN]

I thought it was, just thought I'd ask. I undervolt my CPU but it's Intel so never used curve optimiser.

Can I also ask what cooler you use, I ask because I have a Ryzen system that runs quite hot.

be quiet! Pure Rock Slim (BK008)​

 

[TYPICALHUMAN]

I've found recommended settings for my CPU that reduces performance roughly by 3% and CPU should run noticeably cooler.

PPT = 120, TDC = 75, EDC = 110

I haven't applied them yet as eco mode 65w (enabled in UEFI) performs nearly as good as normal mode in my case and temperatures are much lower 90c vs 76c in AIDA64 stress test.

CINEBENCH R23.200

13308 [MULTI-CORE][ECO]
13677 [MULTI-CORE][NORMAL]

 

[Widow1]

Curve optimizer works fine for me and seems to be safe imo.
I was unlucky and only could get it to -15.
Also limited my CPU to 85C and 85W max.
Using a 7600x
Went from 75C in Valorant to 59C.

You will need to test and find the best magnitude number your cpu supports tho.