POSTStatus

POSTStatus is a standardized way to represent the outcome and progress of the Power-On Self-Test (POST) performed by computer firmware at boot time. It covers codes, flags, and messages used to communicate which hardware checks were performed and whether the system is ready to boot.

The exact presentation of POSTStatus varies by platform. Firmware such as BIOS or UEFI may expose a numeric code, a bitmask, or a textual status, and may emit beeps or LED signaling for early boot. Some systems pass POSTStatus to the operating system or management controllers via debug ports, ACPI tables, or IPMI, enabling software fault reporting and automated remediation.

Common status values describe success or a range of failures: SUCCESS, MEMORY_ERROR, CPU_ERROR, GPU_ERROR, PERIPHERAL_ERROR, NO_BOOT_DEVICE, FIRMWARE_UPDATE_REQUIRED, POWER_FAILURE, OVERHEAT, and UNKNOWN_ERROR.

Historically POSTStatus arose from POST codes used in older BIOSes; today it often appears as part of the broader diagnostic framework in UEFI and embedded systems. It is related to POST codes and beeps, but differs in that it is intended for software interpretation and integration with system management tools.

See also BIOS, UEFI, POST codes, diagnostic LEDs, IPMI.