This is an often asked question.  So, let me begin by saying that you do not "low-level-format" IDE or ATA hard drives. This term is a misnomer from the old MFM hard drive days when a drive could have the tracks and sectors defined using a low level format. 

The IDE or ATA drives we use today have all this information preset at the factory and a real low level format would destroy the drive or at least slow it down radically...  you cannot redefine the tracks and sectors on these drives with a true low level format. Of course this is highly simplified for this discussion, but let us suffice to say that you cannot change the physical geometry of current IDE/ATA drives without destroying it...  or what a low level format does is redefine the tracks and sectors on a hard drive.  So...  this is an old term that really does not apply to today's IDE/ATA hard drives.

Now, with that said, there is a different issue of redefining the logical geometry of the drive, this is done by building partition(s) on the drive.   But, physical geometry of a drive vs. the logical geometry are quite different.

Most people today when they begin using the term Low Level Format have a real problem with an IDE hard drive, otherwise this term would not come up.  Usually, one of the following issues has occurred:

• The drive has a boot sector virus and you cannot access clean it off the drive
• The drive has begun to develop numerous bad sectors and they are increasing, (usually seen when running Scan Disk).
• The drive has had Linux, WindowsNT or another operating system installed creating a Fat System on the drive incompatible with the new operating system to be installed.

So...   you have these problems and you have been told to Low Level Format the drive.  I bet you are puzzled now as to how to proceed?  What you really need to do is what is referred to as reinitialize or mid-level format the drive.  

ReInitializing an IDE Drive
We have the terminology straightened out and you say, "Why does this matter?"  It matters only that you know exactly what we are doing to your hard drive.  When you reinitialize a hard drive, basically you use a utility that over writes the whole drive with ones and zeros.  Every area of the hard drive is cleansed.  

You do this by going to the hard drive manufacturer's web site and downloading the utility they provide for this purpose.  Every drive manufacturer provides just such a utility, though some of them have begun to call it a Low Level Format utility, just so they are not required to explain as I did above.

Once this process is complete, the drive will be void of any partitions.  Now, you will need to use FDISK for Microsoft products to partition the drive and then format the new partition.