Hard Disk Activity Light
The hard disk activity light, often labeled as HDD LED, indicates data read/write operations on your storage drive. It typically blinks when the drive is active, such as during file transfers, system boot, or application usage. A steady or constant blink may signal heavy disk usage or potential issues like a failing drive or high resource consumption.
Power Light
The power light, usually labeled as Power LED, shows the computer's power supply status. It glows steadily when the system is fully powered on. If the light is off, the PC is shut down; a slow blink often indicates sleep or standby mode. Unlike the activity light, it does not reflect disk operations, only power state.
Key Differences
The primary distinction between these lights lies in their functions and behaviors:
- Purpose: The activity light monitors disk I/O activity, while the power light indicates overall power status.
- Visual Cue: Activity light blinks intermittently during drive access; power light remains steady when powered.
- Significance: A flashing activity light suggests normal or high disk workload; a steady power light confirms system power without implying performance issues.
Understanding these differences helps diagnose common problems: For instance, an unresponsive PC with a steady power light but no HDD activity may point to OS errors or frozen applications.
