There is no performance reason to wipe the HD with any more than the quick Diskpart Clean
command, which zeroes the boot sector that sometimes can have corrupt code interfering with Windows 7 install or booting.
Any more than that - using Diskpart Clean All
which writes zeroes to the entire drive, DBAN or the others - only serves to destroy data so that it is unrecoverable by normal methods but not forensics, nothing else. There are always going to be either ones or zeroes there, so forget the whole idea of "erasing" anything.
It took awhile for this to sink in for me: You gain ZERO performance advantage by zeroing the HD. Windows 7 doesn't know the overwritten code is there any more when it overwrites it itself during daily use, than if it has been already overwritten with zeroes.
So Diskpart Clean
Command is sufficient: SSD - HDD Optimize for Windows Reinstallation
More important are the steps you follow to assure a perfect reinstall
, not wiping or "formatting" the HD as though that describes something really extra special clean.