Which SMART attribute ID tracks drive temperature?

• A. Wear_Leveling_Count (SSDs)
• B. Power_On_Hours (ID 9)
• C. Temperature_Celsius (ID 194)
• D. UDMA_CRC_Error_Count (ID 199)

Answer: (C)

The key idea is that SMART uses a set of attributes, each designated to a specific aspect of drive health or behavior. The one that records the drive’s thermal state is Temperature_Celsius. This attribute is specifically designed to capture how hot the drive is operating, and the raw value typically represents the current temperature in Celsius. That makes it the go-to metric for monitoring thermal conditions and for triggering thermal protections if temperatures get too high.

Wear_Leveling_Count, on the other hand, measures how much wear has occurred on flash cells and reflects endurance, not temperature. Power_On_Hours tracks how long the drive has been powered on, which doesn’t tell you how hot the drive is right now. UDMA_CRC_Error_Count monitors data integrity errors on the interface, not the drive’s temperature. So Temperature_Celsius is the correct choice for tracking drive temperature.