Intel has been investigating the source of what it terms "Vmin Shift Instability" since the initial instability reports. The first steps towards a resolution came in August when Intel released its initial microcode updates to address issues with these desktop processors. However, the company admitted it was still searching for the root cause at the time. After months of detailed and "extensive investigations, " Intel has identified four key operating scenarios contributing to the instability.

Apparently it happens under the following conditions:

• Motherboard power delivery settings exceeding Intel’s guidance, which can be fixed by sticking to the defaults. 
•   eTVB microcode algorithm allowing Intel’s Core i9 processors to operate at higher performance states, even at elevated temperatures. This can be mitigated by using the  June 2024 release of microcode 0x125.
•  Microcode SVID algorithm requesting excessively high voltages for durations that trigger Vmin shifts. This is fixed by using microcode 0x129, released in August 2024, which resolved the issue of voltage spikes.
• Microcode and BIOS code requesting elevated core voltages during idle or light activity periods, leading to Vmin shift. Intel is now releasing the comprehensive microcode 0x12B update, which includes the fixes from 0x125 and 0x129.

Intel has  confirmed that its latest 0x12B microcode update is being rolled out through its motherboard partners via BIOS updates. This patch, which incorporates solutions from earlier updates, should help prevent further instability without any noticeable drop in performance. However, Intel has been careful to note that this update will prevent future occurrences of instability but cannot repair CPUs already affected by the Vmin Shift Instability.

For users experiencing issues with affected processors, Intel advises contacting customer service for a replacement through its warranty extension programme. Once a new processor has been provided, Intel recommends installing the latest microcode updates immediately to prevent future problems.