Overclocking feature request

[tweak42]

Unable to set negative values for over_voltage parameter. Value can be entered into field but does not "Set" when pressing button.

According to Raspberry Pi documentation the over_voltage range is -16 to 8

https://www.raspberrypi.org/documentation/configuration/config-txt/overclocking.md

[Jack477]

Thanks for your request, I will add over_voltage range in next update.