A password-cracking expert has created a new computer cluster that cycles about 350 billion guesses per second to crack any Windows PC password. This beast was created using: Five 4U servers 25 AMD Radeon GPUs 10x HD 7970 4x HD 5970 (dual GPU) 3x HD 6990 (dual GPU) 1x HD 5870 4x SDR Infiniband interconnect ...