820-3437 fans spin, no chime

[2informaticos]

Do you get voltage at all big coils?
ALL_SYS_PWRGD present?
Check U1950, pins 7 & 3 for high level.
U1900 is right near U6100, so check all SPI termination resistors and traces for BIOS chip.

 

[ajdoc]

ALL_SYS_PWRGD got 3.29V
U1950 pin 7 and 3 got 3.41V
All SPI was OK.
Replaced U1900 just in case is all working fine again.
Thank you for help - solved.