X64 Exception Type 0x12 Machinecheck Exception Link Jun 2026

: Fatal bit-flips or memory controller errors that ECC (Error Correction Code) cannot fix.

Log into your server's remote management console, such as the HPE iLO Interface or Dell iDRAC.

When troubleshooting a machine check exception on hypervisors or bare-metal setups, standard operating system logs rarely display the root cause. Administrators must extract logs directly from hardware management domains, such as the HPE Integrated Lights Out (iLO) Console or Integrated Management Logs (IML).

The MCi_STATUS register contains an error code that provides detailed information about the failure: x64 exception type 0x12 machinecheck exception link

Comprehensive Guide to Fixing the "x64 Exception Type 0x12: Machine Check Exception" Error

An refers to a Machine Check Exception (MCE) , which is a critical hardware-level error detected by the CPU's Machine Check Architecture (MCA). It indicates that the processor has encountered an unrecoverable internal error, a bus error, or an error from an external agent like memory or a PCIe device . Core Technical Details Exception Vector: 18 (decimal) or 0x12 (hexadecimal).

If the system crashes to a BSOD, it will likely display . : Fatal bit-flips or memory controller errors that

WHEA_UNCORRECTABLE_ERROR (124) A fatal hardware error has occurred. Parameter 1: Bank number (0x3) Parameter 2: MCi_STATUS = 0xfe000000000c0f35 Parameter 3: MCi_ADDR = 0x1a3f0000 **Link: UPI Link 1 - Poisoned packet**

Visually inspect the motherboard VRMs surrounding the CPU socket for bulging, leaking, or discolored capacitors. Summary Matrix: Error Indicators and Targets Indicated Symptom / Log Code Most Likely Physical Cause Recommended Action MCi_STATUS Bank 0 or 1 CPU Internal Cache / Core Fault Lower clock speed, update BIOS, replace CPU. MCi_STATUS Bank 4 / Bus Error PCIe or Interconnect Interruption Reseat GPU, check storage cables, update chipset. Crash under sudden heavy load Power Supply Unit (PSU) Sag Test with a known-good high-efficiency PSU. MemTest86 fails on specific address Defective RAM IC Replace the affected memory kit.

The exception type 0x12 refers to a specific type of Machine Check Exception known as the Machine Check Exception Link. This exception allows for the linking of error records to provide more information about a hardware error that occurred. Core Technical Details Exception Vector: 18 (decimal) or

Memory bus errors frequently report as machine check exceptions.

A Machine Check Exception is a special type of exception that occurs when the processor detects an error in its own operation. This can include a wide range of issues, such as: