Undervolting is one of the more popular changes made when trying to improve battery life. Decreasing the processor's voltage means that less power is consumed, and that translates to better battery life. Typically, users have to wait for a kernel developer to include the feature in a kernel before they can use it. However, that's not the case with the HTC Sensation, as there is now a tool that adds undervolting to any kernel.

Developed by XDA Senior Member D-SHEL, the application uses the popular AROMA Installer to allow users to choose the degree of undervolting used. To change it, users simply need to re-flash the mod and choose a new setting.

To use the mod, it is suggested that users start at -100mV and see if the system is stable, then gradually decrease the amount until stability is found. Users can figure out if it's stable first by checking whether the ROM boots, and second by using a stability app to test. As D-SHEL explains:

Choose -100mV undervoltage first. If phone boots, try system stability test. If all is ok - your chip can handle this UV. If no, flash -87.5mV, try system stability test etc.

For additional info, a link to the aforementioned stability app, and more, check out the original thread.