Hard format

i have an extra laptop hard disc i put it in a usb cover and now i am using it as a usb
i have formated it but i want to completely remove the data that it can not be recover ever
as i can not put it in back my laptop so no software can work on system rebooting
kindly tell me any windows software which can help me complete format this
thanks
Answer #1
There are plenty of apps to securely erase data.
Active@ Killdisk is pretty good. Just choose the right drive.
Despite what companies who sell these programs state about using US defence software and the Guttman method (35 passes) etc (crap) one pass is enough to make things irrecoverable. Governments and Security Services etc don’t bother wasting time using software – they physically destroy the drives.
Depending on the size of the disk – it will take some time.
If you ever want to destroy the data on a laptop drive when it’s installed with no other drives, or a pc, eg. you are selling it, use DBAN, but note there is no option to choose drives, it will just wipe.
*EDIT – you could always just stick it back in the lappy, and use DBAN (boot cd), then put your OS drive back in.
Answer #2
This is another nice freeware app
http://www.wizard-industries.com/sure-delete/