Anyone undervolting the 4090?

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johnnysd

Limp Gawd
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Oct 6, 2007
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My 3080 undervolted great, with actually better performance than at stock. I see some YT videos on undervolting the 4090 or just power limiting it but results seem somewhat mixed.

Anyone doing this? Results you are seeing?
 
Guru3d owners' thread had many seeing great undervolting for the 4090. No extra perf but much lower power draw... They're excellent on efficiency.
 
Yep, especially if you don't have a golden sample. There are cards out there that will only pull 320W at 1100mv at full load doing synthetic benchmarks out the box. But my card is still pulling 350-400W even with a curve topping out at 2675 MHz @ 925mV.
 
Here's my results in my limited testing with Speedway.

Results said:
Volt Limiting
Core OCVRAM OCMax VoltagePower LimitBenchmarkScoreAvg. FPSPeak WattsAvg. WattsPerf DiffFPS/Avg. Watt
FPS/Watt Improvement​
StockStock1050 mV100SpeedWay 4K641264.12431.36411.825Baseline0.1556Baseline
13514001050 mV100SpeedWay 4K678767.87434.7421.35.84%0.1613.47%
13514001025 mV100SpeedWay 4K678767.87434.7413.75.84%0.1645.39%
13514001000 mV100SpeedWay 4K674367.43423.2399.435.16%0.16888.48%
1351400975 mV100SpeedWay 4K666266.62402.3379.73.90%0.175412.72%
1351400950 mV100SpeedWay 4K665666.56386.23633.80%0.183317.80%
1351400940 mV100SpeedWay 4K653465.34375.98352.921.90%0.185118.95%
1351400935 mV100SpeedWay 4K648664.86367.22345.61.15%0.187620.56%
1351400925 mV100SpeedWay 4K645264.52359.9337.80.62%0.19122.75%
1351400915 mV100SpeedWay 4K640764.07354.17331.8-0.08%0.19324.03%
1351400900 mV100SpeedWay 4K631363.13339.6318-1.54%0.198527.57%
1351400895 mV100SpeedWay 4K629962.99335.67315.54-1.76%0.199628.27%
1351400890 mV100SpeedWay 4K629462.94335314.15-1.84%0.200328.72%
1351400885 mV100SpeedWay 4K621662.16326305.18-3.06%0.203630.84%
1351400875 mV100SpeedWay 4K618461.84320.2300-3.55%0.206132.45%
Power Limiting
Core OCVRAM OCMax VoltagePower LimitBenchmarkScoreAvg. FPSPeak WattsAvg. WattsPerf DiffFPS/Avg. WattFPS/Watt Improvement
StockStock1050 mV100SpeedWay 4K641264.12431.36411.825Baseline0.1556Baseline
13514001050 mV100SpeedWay 4K678767.87434.7421.35.84%0.1613.47%
13514001050 mV90SpeedWay 4K672067.2402.2394.54.80%0.17039.44%
13514001050 mV80SpeedWay 4K655565.55358.1354.52.23%0.184918.83%
13514001050 mV75SpeedWay 4K650665.06335.29331.681.46%0.196126.02%
13514001050 mV73SpeedWay 4K639463.94327.24324.11-0.28%0.197226.73%
13514001050 mV70SpeedWay 4K628162.81314.4310.92-2.04%0.20229.82%
13514001050 mV67SpeedWay 4K618661.86301.52298.9-3.52%0.206932.96%
13514001050 mV65SpeedWay 4K598959.89292.4290-6.59%0.206532.71%
13514001050 mV60SpeedWay 4K547054.7270.6267.74-14.69%0.20431.10%
13514001050 mV50SpeedWay 4K418641.86228.4223.1-34.71%0.187620.56%
135​
14001050 mV40SpeedWay 4K300330.03179.7176-53.16%0.17069.64%
Click to expand...
 
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pippenainteasy said:
Can you show your V/F curve? I'm curious how it looks like.
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I'm not home right now but its the method where you just overclock your card like normal, then flatten the curve after the voltage point you want to limit at. My results were me testing the majority of voltage points.
 
I haven't undervolted, just using afterburner and the slider at the lowest is +0.

But I have tried 80% and 90% power targets, which basically cap the power draw. 100% = 443W, 90%=408W, 80%=372W. But all show max gpu voltage was 1.05v.

The temps are good in all scenarios. 67C hotspot, 64C memory at 80%. 73C hotspot, 68C memory for the 100% target. The FE has a pretty amazing heatsink on it.
 
I'm in this thread now also for info and trial my MSI 4090 Gaming X Trio should be in by tomorrow.
 
I overclocked my card up the wazoo. I got 2 fps. What performance are you referring to?
Also card remained at 65 C. What cooler temps are you referring to?

Are there some magical properties of this 4090 that I am missing?
 
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KickAssCop said:
Why though?
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Would be my question. Both the 4080/4090 already run really cool, and aren't really throttling due to heat. If you simply just want the 4090 to use less power wouldn't it be easier to just plug one less power connector on, and force the card to run in 450w max mode?
 
KickAssCop said:
I overclocked my card up the wazoo. I got 2 fps. What performance are you referring to?
Also card remained at 65 C. What cooler temps are you referring to?

Are there some magical properties of this 4090 that I am missing?
Click to expand...
Not sure how locked down 4090s are but for example on a 13900k you can unlock something wild like 20 degrees worth of cooler temperatures which means a cooler longer lasting chip and cooler PC room and lower electricity bill and lower power draw all together. Different ways to tune can go for efficiency or more power with less voltage or find a sweet spot for power and efficiency. For example I can tune my 12700k down to 100 watt power draw and not lose any gaming power. That means my chip stays under 40 degrees under full load if it's a cold day lol
 
What’s everyone using to tune GPU seeing that Afterburner hasnt been updated in a year?
 
I'm going to see if I can download the Asus software and give it a shot as that's what Derbauer was using in his undervoting video.
 
johnnysd said:
My 3080 undervolted great, with actually better performance than at stock. I see some YT videos on undervolting the 4090 or just power limiting it but results seem somewhat mixed.

Anyone doing this? Results you are seeing?
Click to expand...
Ampere was power limited so it was very easy to hit the power limit and have clocks and voltage bouncing around wildly at the max. Hence and undervolt helped stabilize both the voltage and and clock speed. Lovelace on the other hand is voltage limited and unlike Ampere which basically tapped Samsung 8nm for all it could give, Lovelace is much more efficient. Undervolting on Lovelace is probably going to net you better power draw, lower temps, but wouldn't expect to find any unlocked performance via undervolting like you would undervolting Ampere.
 
Undervolting is massive. Watch this video Derbauer made. There are instances where cutting almost HALF the power going into the 4090 only decreased performance by 10% or 35% less power for only a 5% performance trade off. That is a monumentally huge impact on total power draw and temperatures.
 
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I want more performance. Why would I be losing performance? If I wanted a loser card I would’ve bought a 7900xtx.
 
KickAssCop said:
I want more performance. Why would I be losing performance? If I wanted a loser card I would’ve bought a 7900xtx.
Click to expand...
If you can fine tune it well enough you might be able to get the same performance you would have had anyway just with lower voltage and temperature and power draw which extends the life of your components, decreasing your power draw and power bill, lowering your temperatures in case and in your room, lowering your fan speeds making it quieter while being cooler which is all in all a better experience.
Derbauer was just demonstrating that at the cost of 5 percent you can decrease 35 percent power draw or at the cost of 10 percent decreasing almost 50 percent power draw in cases where you don't need the extra power because you are already at the fps limit there is no reason to pump more power/voltage and heat into your pc and room. The 4090 is so powerful that you have that luxury.
 
xDiVolatilX said:
If you can fine tune it well enough you might be able to get the same performance you would have had anyway just with lower voltage and temperature and power draw which extends the life of your components, decreasing your power draw and power bill, lowering your temperatures in case and in your room, lowering your fan speeds making it quieter while being cooler which is all in all a better experience.
Derbauer was just demonstrating that at the cost of 5 percent you can decrease 35 percent power draw or at the cost of 10 percent decreasing almost 50 percent power draw in cases where you don't need the extra power because you are already at the fps limit there is no reason to pump more power/voltage and heat into your pc and room. The 4090 is so powerful that you have that luxury.
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Just use vsync or frame rate limiter so the card is not renderings frames that cannot be displayed on the monitor in a pointless fashion. Meaning you have 100% capability when needed and lower power when not. Not limiting performance at all.

Of course competitive gamers may want uncapped frame rates, 2x over refresh rate if possible (reduced settings, resolution) for lowest input lag.
 
noko said:
Just use vsync or frame rate limiter so the card is not renderings frames that cannot be displayed on the monitor in a pointless fashion. Meaning you have 100% capability when needed and lower power when not. Not limiting performance at all.

Of course competitive gamers may want uncapped frame rates, 2x over refresh rate if possible (reduced settings, resolution) for lowest input lag.
Click to expand...
Yea I already do use G-sync and V-sync because of the reasons you mentioned and I don't like to see any screen tearing. Even on comp shooters I still leave them both on because it's fast enough and I really get distracted by tearing. 4k 144hz is the sweet spot lol
 
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