UK , iv never run into any virus that has survived a reformat.
yes its tru that whan you reformat that all the files are still there , but there "dead" and the OS just sees them as blank space and they can onley be recovered with special file recovery programs.

and that is onley if they havent been overwriten...if somthing new (eg windows)has been written over the deleted files than the files that were there befor are history.

i dont know how much you know about computers UK but please correct me if im wrong...but if you ran into a virus that "survives" a "reformat" you may not have actualy reformated the drive...you may have just done a re install of windows or a "repair install". in wich case the virus would still be there because you dident compleatley erase the drive.

but if im wrong on this and you do know what your talking about and you did run into a virus that survives a compleat reformat, even then , 7 times?? if the virus dose somehow resurect itself, than a zero-fill and 1 reformat should complatley destroy any data/virus on the drive.