'Tis a peaceful night after Christmas, and the ghosts of FDIV and TSX have come once again to haunt Intel. The folks at the Great Internet Mersenne Prime Search (who make Prime95) have come across a bug in Intel Skylake CPUs that causes affected systems to freeze.
The bug manifests when a certain calculation is performed. Prime95 uses the fast Fourier transform to multiply very large numbers, and at least one particular exponent—14,942,209—causes Skylake CPUs to choke. Over- or underclocking the CPU doesn't have any effect on whether the bug occurs.
Intel was quick to track down and identify the issue, and says it's working with motherboard vendors to issue BIOS updates as a workaround:
Intel has identified an issue that potentially affects the 6th Gen Intel® Core™ family of products. This issue only occurs under certain complex workload conditions, like those that may be encountered when running applications like Prime95. In those cases, the processor may hang or cause unpredictable system behavior. Intel has identified and released a fix and is working with external business partners to get the fix deployed through BIOS.
The firm recommends that users contact system manufacturers or motherboard makers for updates.