[SOLVED] Under volting a 5900X

LeVzi

Honorable
Nov 3, 2017
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4
10,585
Hi again everyone, finally upgraded to a Ryzen 9 5900X and really please with it.

I have read up on undervolting the CPU can help on thermals and in some cases give a tiny performance boost.

So I decided to try it out, using PBO.

I am currently at all cores negative value of 30 but I am not seeing any real improvement in thermals.

It's stable running Prime95 small FFT's max temp is 65.

When I run handbrake it goes up to 74 while rendering.

Thing is, those are the same values I got before enabling the undervolt , so I am wondering if it's worth it or not.

Any help is appreciated, and hopefully this is the right place to ask.
 
Solution
Hi again everyone, finally upgraded to a Ryzen 9 5900X and really please with it.

I have read up on undervolting the CPU can help on thermals and in some cases give a tiny performance boost.

So I decided to try it out, using PBO.

I am currently at all cores negative value of 30 but I am not seeing any real improvement in thermals.

It's stable running Prime95 small FFT's max temp is 65.

When I run handbrake it goes up to 74 while rendering.

Thing is, those are the same values I got before enabling the undervolt , so I am wondering if it's worth it or not.

Any help is appreciated, and hopefully this is the right place to ask.
The right way to undervolt with a 5900X is using curve optimizer, not by just lowering core...

Karadjgne

Titan
Ambassador
PBO doesn't do much for the better Ryzens, they are already binned well and towards the top end of performance. The only thing it really does is raise the potential power limits, and if the cpu isn't reaching the stock limits, having raised limits doesn't do anything.

Instead, look into Dram Calculator and ClockTuner2. They work in tandem to raise ram efficiency (important for Ryzens since they work closely with ram speeds and timings) and will also tune the cpu to run at lower voltages. Ryzens are an efficiency engine that works best @ 60°C. It's not only the processor speeds, but the application of the speeds.

My 3700x gets higher performance, lower temps, higher fps at 4.28GHz locked cores and 62°C than it does at 4.4GHz locked cores and 80°C.
 
Hi again everyone, finally upgraded to a Ryzen 9 5900X and really please with it.

I have read up on undervolting the CPU can help on thermals and in some cases give a tiny performance boost.

So I decided to try it out, using PBO.

I am currently at all cores negative value of 30 but I am not seeing any real improvement in thermals.

It's stable running Prime95 small FFT's max temp is 65.

When I run handbrake it goes up to 74 while rendering.

Thing is, those are the same values I got before enabling the undervolt , so I am wondering if it's worth it or not.

Any help is appreciated, and hopefully this is the right place to ask.
The right way to undervolt with a 5900X is using curve optimizer, not by just lowering core voltage. Not even using negative offset.

The boost algorithm is temperature seeking so it will always try to reach the same temperature but with an undervolt it hits same temperature at higher clock frequencies. So you should expect to see the same or similar temperatures but with better performance.

If you are using curve optimizer try running some controlled benchmarks...Cinebench 20 or 23 are good. Both single thread and multi-thread. Compare them to running the exact same way with and without your curve optimizer undervolt.

Your current temperature during a Handbrake video render (74C) is really quite good so you should be able to get decent performance uplift with curve optimizer.
 
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Solution

LeVzi

Honorable
Nov 3, 2017
134
4
10,585
Yeah I agree, looking into per core undervolting , its beyond my remit lol I am not confident to go that far tbh, i'm going to leave it as it is, 76 degrees for an hours rendering is fine by me, in a warm room.