I have a 3410 so I don't know if there is any difference to the 3810 but when I flashed 1.24, there was no saving in power and the fan was spinning permanently on battery.

I reverted to 1.17 and the laptop is nice and quiet again.

BTW, if people would like to know how to flash an older version, there is a DOS flashit option /mc, which ignores version checking.

flashit JM3100FR.117 /mc
It looks like the little script accepts one option, so this may work too:

f.bat /mc