We urge computer users to construct strong passwords, and may employ technological controls to prevent them from creating passwords that don't include lowercase, uppercase, numerical and special characters - but is it really enough? Once upon a time, following these rules would go a long way toward protecting you against a brute force attack, but that was before the advent of inexpensive GPUs. Graphics Processing Units are designed to speed up the rendering of images to be displayed on a computer monitor, but modern GPUs can be used for performing the processing that's traditionally handled by the CPU. There's even a name for this, General Purpose Computing on Graphics Processing Units, or GPGPU.
Unfortunately, these powerful GPUs can be used by attackers to crack strong passwords, using free tools that are available on the Internet. And they can do it far more quickly than with a regular CPU. Find out more about this threat here: