Q: Eight myths about energy efficient office equipment
Myth 1: When equipment is turned 'on' there is a power surge so large that leaving your equipment 'on' consumes less energy.
Reality 1: If present (which is not always the case) then the duration of this power surge is so small (seconds) that it is comparable to a few seconds in "on' mode. Whenever your equipment is not used for a few minutes, it makes sense to turn it off or (let it) switch to a low power mode.
Myth 3: Frequent turning off computers crashes the harddrive
Reality 3: Switching off computers will have no significant effect on the useful life of a harddisk. Today manufacturers specify some 40,000 power cycles for a harddrive, equivalent to 30 start/stop cycles for each working day over five years.