820-3115 no post

[MOMOH]

Have got an 820-3115 , with no cpu activity . the machine goes on and the DRIVE LED REMAINS ON . I could not pick up anything except that L7550 is 0V , schematic says should be 1.5V. So am not sure if that is my problem or that the signal is not present because the board is not posting ...Also R7555 is 0V on both sides , am not sure if thats okay as well. did replace U7400 , but nothing changed

 

[2informaticos]

L7550 is for integrated graphics and usually no voltage there; unless high graphics load is present.
Do you get voltage at L7510/20?
Check R7402/03.
You didn't post anything about other S3 and S0 voltages.

 

[MOMOH]

Thank you for your response, I get voltage on L7510 and L7520... on R7402 I get PPBUS voltage on pin 1 and less than 1V on pin 2 , on both TOA & B

 

[MOMOH]

Thank you so much for this info , I appreciate

 

[MOMOH]

I would like to know, whenever a PGOOD signal is present on a particular chipset, I suppose that means everything is okay on that chip right ?