Gigabyte Z790 S WIFI DDR4 User Manual page 18

Status LEDs
The status LEDs show whether the CPU, memory, graphics card, and operating system are working properly
after system power-on. If the CPU/DRAM/VGA LED is on, that means the corresponding device is not working
normally; if the BOOT LED is on, that means you haven't entered the operating system yet.
CPU: CPU status LED
DRAM: Memory status LED
VGA: Graphics card status LED
BOOT: Operating system status LED
CPU DRAM
VGA BOOT
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