Low Level Format is technically not a good name for what you are talking
about. It is pretty much impossible to do a true low level format on
modern harddrives. What actually happens with these so called "low
level format" utilities, is that 0's are written to all sectors of the
harddrive. This is actually a zero fill utility and not a true low
level format. This erases all data on the drive and is very fast and
efficient. Now if you want to really scrub that sucker, check this out: http://www.ontrack.com/dataeraser/