User Guide

Chapter 3: Motherboard Information
3-8
3.3 Onboard LEDs
1. Diagnosis LEDs
The Diagnosis LEDs provide the status of these key components during POST (Power-
On-Self Test): CPU, memory modules, VGA card, and hard disk drives. If an error is
found, the critical component’s LED stays lit up until the problem is solved.
2. CATT ERR LED (CATTERR1)
The CATT LED indicates that the system has experienced a fatal or catastrophic error
and cannot continue to operate.
The Diagnosis LEDs provide the most probable cause of an error code as a starting point
for troubleshooting. The actual cause may vary from case to case.