I have backed up and formatted a thousand computers and not once re-installed the infection on the clean install. most infections are located in the "windows" or "windows\system32" or "all users\application data" or "temp" directories. If you back-up docs and pics and e-mails etc you are pretty safe. I see what you are saying, but in the time it takes to run 1 malwarebytes scan on a infected 200GB hard drive, I can back-up data, format, re-install and restore data, Done. Never mind having to run 3 or 4 more different programs to make sure the infection is gone.