Forget passwords. They are obsolete now that passwords are easily guessed by cheap hardware. An article by Adrian Kingsley-Hughes published in ZDNet describes the ease with which an inexpensive graphics processor unit (GPU) can guess a password.
For instance, “a password of ‘fjR8n’ can be broken on the CPU in 24 seconds, at a rate of 9.8 million password guesses per second. On the GPU, it takes less than a second at a rate of 3.3 billion passwords per second. Increase the password to 6 characters (pYDbL6), and the CPU takes 1 hour 30 minutes versus only four seconds on the GPU. Go further to 7 characters (fh0GH5h), and the CPU would grind along for 4 days, versus a frankly worrying 17 minutes 30 seconds for the GPU.
“It gets worse. Throw in a nine-character, mixed-case random password, and while a CPU would take a mind-numbing 43 years to crack this, the GPU would be done in 48 days.”
The article may be found at http://www.zdnet.com/article/cheap-gpus-are-rendering-strong-passwords-useless.