Cmos battery does not fix physically bad motherboard.
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The Diagnostic LEDs remain 1, 2, 3, 4, and placed on the front of the unit.
Diagnostic LED numbers 1, 2, & 3 are illuminated. Power button LED is solid amber. A possible coin cell battery failure has occurred. Remove the coin cell battery for one minute, reinstall the battery, and restart.
Diagnostic LED numbers 1 & 2 are illuminated. Power button LED is SOLID amber. A possible system board failure has occurred. Disconnect all internal and external peripherals, and restart the computer. If the computer boots, add the peripheral cards back one by one until you find the bad one. If the problem persists, the system board is probably bad.
Diagnostic LED number 1 is illuminated. Power button LED is SOLID amber. A possible system board failure has occurred. Remove all peripheral cards from the PCI and PCI-E slots and restart the computer. If the computer boots, add the peripheral cards back one by one until you find the bad one.
Diagnostic LED numbers 1 & 4 are illuminated. Power button LED is SOLID amber. Power connector not installed properly. Reseat the 2x2 power connector from the power supply unit.
Diagnostic LED number 2 is illuminated. Power button LED is Solid amber. Possible peripheral card or system board failure has occurred. Remove all peripheral cards from the PCI and PCI-E slots and restart the computer. If the computer boots, add the peripheral cards back one by one until you find the bad one.