I saw a reddit post about the RTX 4060TI Undervolting Potential (but the answers are seems unsatisfied, and not much to talk about).
TL;DR – Undervolt can achieve 100W or less with the almost the same clock speed (2760-2770MHz). But at the lower clocks, it is more efficient to only underclock the card. It cannot set the voltage below 0.86V (on my MSI GPU)
I bought RTX 4060TI 16GB (for 355USD) mostly considering the power efficiency and and the out-of-the-box features for programming (beyond gaming) and such.
I undervolt my GPU, and I use Forza Horizon 4 Benchmark Hardware Unboxed: Optimized Settings. (I tried to set the ultra max settings, the power consumption results for different presets are added by 20 Watts each.
I used the preferred UV method by Superior 85 Youtube channel for his RTX 4070.
Then, I tried multiple presets including underclocking. I want to know the Lowest Power Consumption.
Comparing to the Main Stock Settings, the UV-A (GPU Clock: +220MHz; 2760MHz @ 0.97), and UV-B (UV-A (GPU Clock: +240MHz; 2760MHz @ 0.96) improves the efficiency by 21-25%.
But, when I tried to overclock the Memory, the Framerate results are insignificant, it only increases power. So I set it to default +0 MHz.
I Undervolt and Underclock the GPU. It still generally reduces the power consumption with minimal performance losses.
But Something weird when I Compared to the Stock-Underclocked Settings, it has better efficiency than Undervolted-Underclock.
I tried to further underclock, and undervolt the GPU. But the minimum voltage can be set is 0.86V on my MSI RTX 4060TI. I don't much know to the other partner cards or even the founder's edition.
RTX 3000 GPU such as RTX 3080 can undervolt upto 0.725V.
RTX 4060TI has the good undervolting potential.
When the clock frequency is kept similar to the stock settings with lower voltage, the power efficiency improve upto around 100W, sometimes sub-100.
When it combines with underclocking, it also saves much power. However, it is more power efficient to only underclock it with the stock voltage settings.
Something I learned, that changing the frequency without changing the voltage will also slightly affect the power consumption.
The lowest voltage can set is 0.86V. I tried to use "force constant voltage", but no changes.
In the end, I'm happy with my results. I underpower my GPU because it is too fast compared to my integrated graphics, and I want to save the power consumption. I will use the full power whenever I needed.