A further improvement is to enforce these constraints with types, e.g., types.int or whatever is appropriate in this case.

Should the temperature targets also be negative integers?

Also, what does a value of "-2" represent? 2V? .2V (aka 2 decivolt)? 2 arbitrary steps on some scale? Would be nice to get that documented as well. (Same with temperature, probably in degrees Celsius, but would be nice to get that explicit as well)

Could change the type to types.strMatching "-[0-9]+" instead of types.str. Like @joachifm it seems that an integer type would be nicest but I guess string may have to do for backwards compatibility reasons?

Of course a proper integer type would be best, but it's a breaking change and I don't know how those are dealt with here.

@Synthetica9 Yes, they should be negative integer values. My config:

undervolt = {
  enable = true;
  coreOffset = "-80";
  gpuOffset = "-90";
}

corresponds to the command undervolt --core -80 --cache -80 --gpu -80. (The config links cache and core, but this isn't documented either.)

The values are in mV, which I agree should be documented as well. I suggest updating the text to say "[...] voltage (in mV) [...]".

@jarlg You don't use temp, tempBat, or tempAc in your config...? Am I missing something here? What do these values represent?

@Synthetica9 No, I am happy with my laptop's default (97C ). The CPU (or GPU) is throttled upon reaching these temperature thresholds.

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