Huh, sorry if it seems scary, it really isn't so bad. Honestly, now that I understand how Linux exposes these settings, undervolting makes a little more sense in that world.
Ignore the undervolting stuff for a second, and go back to your regular understanding of overclocking a card. When you use the little "clock slider" to overclock your card today, let's say you set it at +105MHz, what you've done is moved the entire voltage curve up by that clock amount -- just like when my instruction above grabbed the one little dot and moved it up. Now all you need to do is limit the upper clock speed of the GPU so it stays parked at the lower voltages. In MSI Afterburner, you cap the GPU clock speed by changing the voltage curve into a perfectly flat horizontal line, like I showed above with the CTRL+SHIFT+ENTER key combo.
In Linux, we actually use the overclock slider just as I described above, then we use a command to cap the maximum speed of the card (nvidia-smi -i 0 -lgc 210,1905 would cap the maximum speed to 1905MHz but would also allow to fluctuate all the way down to 210MHz when its not under load.) In my mind, it's easier to undervolt in Linux versus Windows, with the notable mention of NVIDIA driver installation and configuration on Linux can be a huge pain in the ass, even moreso for cards which do not have a display directly plugged into them!!
Anyway, I hope you consider trying it some time. There's nothing scary or hard about it, the card will reset if you get a little to aggressive with undervolting. The great news is, you're under-volting the card, so there's nothing damaging about it.
