Overclockers: Why You Should Undervolt Your Graphics Card.

[Thinder]

On 1/9/2023 at 12:58 PM, Burt said:

Well I think it’s mostly for temps and frequency/ throttling. I have been running an undervolt the last few months now that lowered my gpu temps and vram temps and also frequency numbers are higher and stays put.

That's the whole idea; to eliminate the risk of cpu/gpu reaching their thermal limits and throttling back under load, same as for using Cl14 RAM for Ryzen 3/3Ds.

I use PBO2 tuner for the time being, I don't think there is a viable BIOS option for undervolting the AMD Ryzen 7 5800X 3D, so I do it in Windows, it seems to work, although I haven't bothered checking on the exact data for results, the undervolt level is -15v/core and my system is stable even in multi-players missions.

[VR Flight Guy in PJ Pants]

Update: 920mV is a bit stable, DCS World crashes in VR, probably for a number of reasons, but I add 10 more mV for safety:

Edited January 15, 2023 by VR Flight Guy in PJ Pants

[Lurker]

I want to undervolt my RTX3090 (non Ti) in order to get it to use a little bit less power (50 Watts less would be ideal). I assume I can do that by lowering the power curve a little bit to drop the max Mhz and then undervolting it so it can run stable at that speed? Am I getting this right?

[edmuss]

1 hour ago, Lurker said:

I want to undervolt my RTX3090 (non Ti) in order to get it to use a little bit less power (50 Watts less would be ideal). I assume I can do that by lowering the power curve a little bit to drop the max Mhz and then undervolting it so it can run stable at that speed? Am I getting this right?

Not quite, find the clock speeds and voltage that you're achieving on stock settings, lower the entire curve as much as possible (using the core clock slider) and then use the curve editor to drag the same clock speed up at a lower voltage.

So if you're achieving 1950mhz @1050mv on stock settings, lower the entire cuve and then select the curve point at 950mv and drag it back up to 1950mhz, hit apply and then it should flatten the curve after 950mv.  Test it, if it's stable and you're happy with the temps/power then try increasing the clock speeds by dragging the same voltage point up by 15-20mhz. Rinse and repeat till you find the sweetspot balance of power, heat and performance.

My asus 3080ti TUF on stock clocks boosts up to about 1800-1850mhz whilst pumping up to 1080mv into it, with a 975mv undervolt I can set the clocks to 2040mhz and it sits there pretty consistently and temps are around 65°C.

 

[LucShep]

On 1/19/2023 at 10:38 AM, Lurker said:

I want to undervolt my RTX3090 (non Ti) in order to get it to use a little bit less power (50 Watts less would be ideal). I assume I can do that by lowering the power curve a little bit to drop the max Mhz and then undervolting it so it can run stable at that speed? Am I getting this right?

Try one of these three (or similar) on your RTX3090 (non Ti) using MSI Afterburner.:

1800 Mhz core frequency @ 831mv
or
1845 Mhz core frequency @ 850mv
or
1860 Mhz core frequency @ 856mv

If necessary to adjust core values for whatever reason, decrease/increase in steps of 15 Mhz, in the core clocks graph curve of MSI Afterburner.

In addition, you can also safely overclock your memory up to 1312 Mhz (that's 20.992 Gbps effective). Which translates to +748 in the memory value setting in MSI Afterburner. 
Note that the stock memory is 1219 Mhz (19.5 Gbps effective). So, doing this adjustment in the memory puts it right in the ballpark for what the Micron GDDR6X memory in the RTX3090 is rated for from factory (21.0 Gbps effective) - good gains added, no stability issues.

From there on, it's all diminishing returns.

The undervolting core frequency values won't differ much (if at all) from one specific model of RTX3090 to another. At least for my EVGA RTX3090 FTW Ultra, those values are certainly the sweetest spot (fully stable, cool and performant) that I've stress tested, among so many other combinations, in benchmarks and games (including DCS).

Expect very small but noticeable performance gains (~5%), all the while you're running far lower voltage (~100W less) and quite a bit cooler (over 10ºC cooler).  

For example, with Heaven Benchmark @1080P Ultra...

• All stock settings: score 5980 (+/-), 430W peak GPU Power, 90ºC Mem Junction temp (highest overall temp)
• After Undervolting: score 6290 (+), 340W peak GPU Power, 78ºC Mem Junction temp (highest overall temp) -  1845 core / 1312 mem @ 850mv

It's a "Win Win" !!  

FWIW, a very quick tutorial on "how to undervolt":

 

Edited January 24 by LucShep
added video

[Lurker]

@LucShep thank you! That's just what I needed. Will give your settings a go. 

[Burt]

I’m really liking my 3090 undervolt and have been running it for 2 months now. I find it for some reason more stable when msi-af is running in the background when playing dcs. 
 

-200 on the core clock - 950mv to 1935mhz 

[Lurker]

Im a complete retard. Please, for the love of god where is the "confim button" on the MSI Afterburner Curve page? I can drop the curve to my desired clock speed, but when I need to raise the dots to my desired voltage I can't figure out what key to press?

In the video above he says "press confirm" press what to confirm? Also google seems to be clueless and MSI's homepage is even more useless in this regard. 

Edited January 23, 2023 by Lurker

[tomcat_driver]

1 hour ago, Lurker said:

Im a complete retard. Please, for the love of god where is the "confim button" on the MSI Afterburner Curve page? I can drop the curve to my desired clock speed, but when I need to raise the dots to my desired voltage I can't figure out what key to press?

In the video above he says "press confirm" press what to confirm? Also google seems to be clueless and MSI's homepage is even more useless in this regard. 

 

There is no confirm button. Just go back to AB's main window and click "Apply". (1)

Don't forget to save the new Preset. (2) and (3)

Edited January 23, 2023 by tomcat_driver

[Lurker]

Just wanted to post a thank you to the people who have helped me out in this here thread. Thanks! 

Quick question, I just downloaded new nvidia drivers, do I need to go through the whole procedure again or do I just reload my profile? Will it reload my profile automatically on reboot? Thanks again!

Edited February 9, 2023 by Lurker

[Hiob]

16 minutes ago, Lurker said:

Just wanted to post a thank you to the people who have helped me out in this here thread. Thanks! 

Quick question, I just downloaded new nvidia drivers, do I need to go through the whole procedure again or do I just reload my profile? Will it reload my profile automatically on reboot? Thanks again!

 

With Afterburner? No the Nvidia-Driver update doesn't make any action neccessary.