Removing the battery does'nt necessarily mean that the BIOS settings will be lost if no back up is made first. It depends on the amount of time that goes by when the battery is removed and a new one is put in. If the replacement is done quick enough, then no settings will be lost. And besides, if the Real Time Clock is losing time, then that means that the BIOS settings are probably being lost already. Its better to just make a record of the BIOS settings first before replacing the battery, instead of backing up. That way if the BIOS is lost, all settings can be re-entered manually.