Older CPUs (pre-Nehalem) or ARM64 systems do not expose link details. Ensure you are using mcelog --ascii or rasdaemon on Linux and that your kernel has CONFIG_X86_MCE enabled.
The is a critical architectural halt state triggered when an x86-64 processor detects a severe, unrecoverable hardware or bus communication failure. Unlike standard software crash dumps, an MCE bypasses regular operating system exceptions because it indicates that the underlying silicon or interconnected fabric cannot guarantee reliable calculation data. On enterprise hardware, such as the HPE ProLiant Server Line , this exception often forces a system crash resulting in a vivid Red Screen of Death (RSOD) or an immediate hardware reboot. Anatomy of an Exception 0x12
The x64 Exception type 0x12, or Machine Check Exception, can occur on a ProLiant DL380 Gen10 server. This error can indicate that: Hewlett Packard Enterprise Community
An x64 Exception type 0x12, or Machine Check Exception (MCE), is a critical hardware-level signal indicating the CPU has detected an unrecoverable internal or bus error, often presenting as a server RSOD or PC BSOD. Common causes include overheating, unstable overclocking, failing hardware, or firmware mismatches, with troubleshooting focused on updating BIOS, resetting configurations, and running hardware diagnostics. For more details, visit HPE Support . x64 Exception type 0x12 in ProLiant DL380 Gen10 Server x64 exception type 0x12 machinecheck exception link
HARDWARE ERROR. This is not a software issue. CPU 0 BANK 3 MCG status: MCi_STATUS=0xbc000e000f000315 MCE: 0x12 MISC: 0x86 ADDR: 0x7fb3c0000 TIME: 1703000000 LINK: 0x1 (Interconnect: UPI Link 0)
: Fatal degradation of the physical bus linking multi-socket CPU systems.
Reseat or replace memory modules if the error points to a specific memory slot. Hewlett Packard Enterprise Quick Reference Table Likely Cause Recommended Action Voltage drop or logic error Update BIOS; Set "Max Performance" profile Uncorrectable ECC error Memory Diagnostics ; Reseat DIMMs Firmware incompatibility HBA/NIC drivers and firmware Overheating under load Increase fan speed/Cooling profile Could you tell me a bit more about the environment where this is happening? For example: What is the hardware model (e.g., HPE ProLiant, Dell PowerEdge)? Did this occur during or while the system was under load Do you have access to the System Event Logs code from the error logs. x64 Exception type 0x12 in ProLiant DL380 Gen10 Server Older CPUs (pre-Nehalem) or ARM64 systems do not
While software bugs rarely trigger an MCE, hardware, firmware, and low-level drivers frequently interact to spark an 0x12 error:
Sometimes this is a temporary condition, particularly if caused by a minor PCI initialization issue.
Unstable power supply leading to incorrect electrical signals, causing errors on the motherboard or CPU. 3. Troubleshooting and Fixes Unlike standard software crash dumps, an MCE bypasses
When an x64 processor encounters an error it cannot recover from via standard error-correcting code (ECC), it leverages its to broadcast a warning. The x64 vector 0x12 points directly to an #MC (Machine-Check) exception .
The bug check 0x124 stop code appears with four parameters that provide critical diagnostic information:
What (Windows, Linux, ESXi) experienced the crash?
Bit-flips in RAM (often detected by ECC memory but fatal on non-ECC sticks) will trigger an MCE if the CPU receives corrupted data.
Have you decoded a 0x12 exception recently? What did your MCi_STATUS register show? Let me know in the comments.