NVidia's GeForce 8800 graphics card could be utilised to "dramatically" reduce the time needed by hackers to perform brute-force password cracks, security experts have warned.

Moscow-based IT security software vendor Elcomsoft claimed that the GeForce 8000 could be used to increase the speed of password cracking by a factor of 25.

This means that Windows Vista's password system, which would normally take months to crack using a brute force technique, could be broken in a matter of days.

Calum Macleod, European director at data encryption firm Cyber-Ark, explained that this reduction is down to the parallel processing capabilities of the nVidia graphics processor.

"Elcomsoft's revelations are likely to send shock waves through the IT security world, as it shows that powerful off-the-shelf kit can be now used for advanced hacking procedures," he said.

"If ever there was a wake-up call to companies of the need to encrypt their data, this is it."