said by SweetNoob :
I know about hardware malware being specifically designed for certain manufactures..
Had a hardware supplier (motherboard or Hdd...forget) allow for a hidden partition for it's own recovery. It was not searchable on the OS and not formattable by standard methods. Combined with a simple MBR exploit i would have to guess whether any malware has been written to exploit it. The malware in a hidden partition may not be scanned by AV.
Checking for these partitions can usually be assumed by comparing harddrive space from actual Hdd size.
I have a non-OEM install for a non-laptop Hdd so using D-Ban or equivalent should suffice in wiping the total drive space that these could hide.
O.k. forget d-ban for this job.