For example: C:\ffcache or D:\Firefox\diskcache to move it to another hard drive.
Then for the string value, type the new location for the cache directory and click OK.In the New string value box, enter _directory for the preference name and click OK.On the config page, right click anywhere on a blank space and select New \ String.Just type about:config in the address bar (location bar) and click on the ' I'll be careful, I promise!' button (to acknowledge the warning message).
