Question 3900x low voltage OC question and what did you get?

wehler53

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Dec 30, 2013
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Hi all,

Im playing around with low voltage OC on my ryzen 3900x after seeing this https://www.pcgamesn.com/amd/ryzen-9-3900x-overclock (basically only 6% can sustain 4.2 all core at 1.25v as per silicon lottery).

Im currently stable at 4.2 1.225V, im curious particularly to anyone else for their low voltage OC's what you achieved. And what temps you were seeing?

But also thoughts on whether its worth running this OC vs Auto settings and a lower offset?
 
I have the 3700X. But I'm curious about the 3900X performance and OCing.

You have "OC'd" it to 4.2GHz?? What does it run at on default settings for an all-core turbo boost according to your system, not the manufacturer specs? Seems like it would do better than that, but...

Is your goal lowest voltage or best performance?

My 3700X runs best on default settings (around 4.3GHz all-core), but it also uses 1.5V. Temps are good though, typically around 55C gaming Update with NZXT Kraken X62.
 
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wehler53

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Dec 30, 2013
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I have the 3700X. But I'm curious about the 3900X performance and OCing.

You have "OC'd" it to 4.2GHz?? What does it run at on default settings for an all-core turbo boost according to your system, not the manufacturer specs? Seems like it would do better than that, but...

Is your goal lowest voltage or best performance?

My 3700X runs best on default settings (around 4.3GHz all-core), but it also uses 1.5V. Temps are good though, typically around 55C gaming.

3.8 is standard clock, with up to 4.6 on two cores (with boost), im focusing on low temp all core 100% oc atm, im at 55 degrees after 2 hours 100% load, i want to avoid going over 1.25v because of depreciating life of the cpu when used daily above that voltage. 4.3 might be possible at 1.25, 4.2 @ 1.2 would be nice to see for good performance at low temps and low power usage.

All core boost is around 4.1 - 4.2 @ around 1.35v stock from what ive seen
 
3.8 is standard clock, with up to 4.6 on two cores (with boost), im focusing on low temp all core 100% oc atm, im at 55 degrees after 2 hours 100% load, i want to avoid going over 1.25v because of depreciating life of the cpu when used daily above that voltage. 4.3 might be possible at 1.25, 4.2 @ 1.2 would be nice to see for good performance at low temps and low power usage.

All core boost is around 4.1 - 4.2 @ around 1.35v stock from what ive seen
What cooler do you have?
 

wehler53

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Are you leaving the clock speed on auto while undervolting?

Are you running benchmarks after each adjustment to make sure performance isn't affected by lowering the voltage?

I am manually setting the clock, 3900x's from what ive read are having issues with hitting their 4.6 single core and only hitting 4.2, that was what i saw, even letting it have access to over 1.45v when it wanted. Im running sustained loads using Prime95 and Heavy load, and running 10 cinebench R20 tests per clock change, 4.2 @ 1.2 was stable underload but unfortunately didnt pass the real world tests i hit it with, 1.225v was stable across 20 R20 tests and is currently at 8 hours blend test on prime95, performance is 7000 vs 7500 on R20 (stock vs under volt OC) temps are about 4-5 degrees lower and much more stable due to the removal of the boost seetings which in my opinion and from testing are trash.

Id love to hear from other 3900x users if you are also only seeing 4.2 on boost and not 4.6
 

Mwalimu Nyoka

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Feb 3, 2020
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Hi all,

Im playing around with low voltage OC on my ryzen 3900x after seeing this https://www.pcgamesn.com/amd/ryzen-9-3900x-overclock (basically only 6% can sustain 4.2 all core at 1.25v as per silicon lottery).

Im currently stable at 4.2 1.225V, im curious particularly to anyone else for their low voltage OC's what you achieved. And what temps you were seeing?

But also thoughts on whether its worth running this OC vs Auto settings and a lower offset?


I have a 3900x on a gigabyte ultra X570 with 32 gigabytes of corsair vengeance 3200 DDR4
I've been able to get a rock solid 4.3 ghz manual all cores with 1.18126 voltage CINebench r20 around 7330 consistently. Idle around 37 c. Work from home around 40-43. Game with a 5700Xt red devil around 52-55 most games. get up to around 63C on cinebench with a coolermaster 360mm. Interestingly, I have only gotton up to 4325 staying stable on 300 seconds of cinebench at 1.325 voltage. I'm new to this butI stopped trying as I prefer the lower voltage given the marginal difference (it only bought me 50+ points in cinebench)