"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 behaviour."
Intel has developed a fix, and is working with hardware partners to distribute it via a BIOS update.
No reason has been given as to why the bug occurs, but it's confirmed to affect both Linux and Windows-based systems. Prime95, which has historically been used to benchmark and stress-test computers, uses Fast Fourier Transforms to multiply extremely large numbers. A particular exponent size, 14,942,209, has been found to cause the system crashes.
While the bug was discovered using Prime95, it could affect other industries that rely on complex computational workloads, such as scientific and financial institutions. GIMPS noted that its Prime95 software "works perfectly normal" on all other Intel processors of past generations.
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Intel looking into reports, but says there "could be several variables at play."
While this particular bug can be fixed via a BIOS update, we are reminded of another famous bug that plagued Intel's original Pentium processor that couldn't be so easily rectified. The Pentium FDIV bug—discovered by Thomas Nicely, a professor of mathematics, on October 19, 1994—was a floating-point divide problem caused by a circuit design error.
While the flaw would rarely have been encountered by average users, extensive media coverage ultimately led to Intel recalling the defective processors.
Mostly recently, Intel's Haswell and early Broadwell processors suffered from a TSX (Transactional Synchronization Extensions) bug. Rather than recall the parts, Intel disabled the TSX instructions via a microcode update delivered via new motherboard firmware.