Here is a quick setup for
Afterburner undervolting. This guide is not meant to answer the question Why, but rather How. If you are interested in undervolting then you may have a number of different goals in mind. Reduce heat, reduce power, or just love tweaking your GPUs... This process also works on older generation cards, but the focus here is Ampere.
Basic Steps Reset everything in Afterburner. For best repeatable results, make sure the GPU temp is around 34C when setting the undervolt.
1) Type -250 in the core clock box and hit ENTER
2) Click the check mark
3) Click the Curve Editor and drag the curve popup so you can still see the main Afterburner screen at the same time.
4) Drag a point up by clicking on the dot and dragging with your mouse. I chose 0.950V and dragged it to 1890MHz. This is a good starting point for most Ampere cards. Just to get started.
5) Click the check mark on main Afterburner window. The curve shifts up and flattens out after your selected point.
Close the Curve Editor popup (X it out). You should now see this with "Curve" where there used to be a Core Clock offset of -250. Ready to bench.
Additional comments - Why choose a Core Offset = -250? Because this number works for most scenarios. This setting shifts the entire curve down all at once. If the curve isn't shifted down far enough, then the curve will not be completely flat after step 5. Try some different values and see for yourself. Note: A flat curve is critical to making this process work, keeping the card voltage fixed at your chosen value because there will be no higher options available along the curve past that point.
- From here you test for stability using stress tests. My own experience is that 3DMark Firestrike Extreme stress test will give solid results. Once you reach stability, then use your favorite benchmarks to compare the stock results to your undervolted results. This is how you will know that a given undervolt/clock gives you performance results on par with stock...
- General methodology. 1) You can keep reducing voltage while maintaining the 1890MHz core in an effort to find the lowest voltage setting possible. 2) You can increase clock at the same 0.950V in order to find the highest clock at that voltage. Note: Changing both at the same time makes the results hard to track, I recommend changing only one setting at a time.
Here are some things to note in each case.
1) Lowest voltage search. Lower voltage in steps of 0.006V or 0.012V at a time (up to you, use 0.012 as a coarse step and then tweak with 0.006 as you encounter crashes). You will eventually reach the lowest voltage for your clock setting. When you reach instability, try to reduce clock and try that same voltage again. If it still doesn't run stable, reduce clock another step. At some point you may never be stable and this would be considered the lowest possible voltage. Note: You should decide how low you are willing to go with clock setting based on your goals. IMO there is no reason to make the card perform worse than stock, so work first to find the fixed clock that gets you par stock performance, then aim for lowest voltage at that clock.
2) Highest clock while keeping volts as low as possible. Keep increasing clocks step by step* for a given voltage until you go unstable. Then increase volts at that clock until you are stable again. Then go up in clock until you are unstable at that voltage. Continue in this stair step fashion. You will eventually reach a ceiling where you cannot achieve stability. This point will coincide (generally) with the fact that additional voltage will only result in throttling and more heat, or continued crashing. *Note: Actual clocks will snap to the nearest permissible step for your card. Example, drag to 1896MHz and it will snap to 1890MHz once you hit the apply button (check mark). Most cards step 15MHz, although I have seen some allow 7-8MHz.
- You will get better temps with manual fans cranked up, but try to test on Auto at first... then push it with more airflow once you have the baseline data. If your clock setting ends up lower while benching (downclocking), then the card is throttling for heat or power... this is where more fan can sometimes help.
- Keep track of your settings and results in a text file or spreadsheet. Write down at least the clock and voltage settings, avg peak temps, power consumption, fan settings, and clock throttling observations.
GPU-z is helpful here... enable data logging.