Another optiplex 380, MB 0HN7XN , fault - dead,
found attached shematic is corresponding, there are same SCH5514E and SB ICH7 NH82801GB


It has 3.3Vstb supply to SCH5514E and SB, but does not reacting to PWR Button
PWRBT signal is ok when pressed BT, it goes from 3.3V to 0V

Bios is not problem !
Heating SB does not help.

PWR_PS_ON is at 5V all the time, PSU_PG 0V
SIO_RSMRST is high 3.3V, but SLP S4 S5 and SLP S3 are 0V
no change after PWRBT press
measured reset signal coming from SB, PLTRST -> SIO_LRESET is always 0V

is possible problem with SB ICH7 ?

Thanks!

VCCRTC ? XTAL 32.768KHZ works ?

VCCRTC 3.3V, 32.768KHz OK