Power on secuence on motherboard?

[Stever]

The other half of the time is failed BIOS's that will need replacement or reprogramming off-board (so you'll need the requisite programmers and ROMs, etc.

Once upon a time many years ago even the most screwed up bios would default to booting from the A: floppy and an ISA graphics card to enable a re flash.

 

[Stever]

Hi, guys!

I'd like to understand power on secuence of motherboards, so I can diagnose them and fix them properly for repairing. Where do I have to start studying? Any suggestions, guys? Books for reading or something else?

Greetings!

It's not just the power on sequence !
Modern motherboards may have a ridiculous number of layers internaly with blind buried via's, not just what you can see on the top and bottom !
Typical track widths can be .005" or less for internal layers and BGA, if you have a cracked internal track or via then there is nothing that can be done about it !

 

[Stever]

Electronics Channels on YouTube that I frequent:
Louis Rossman Macbook repair videos
EEVBLOG
Contextual Electronics
mikeselectricstuff
Fran Blanche
HACKADAY
RSD Academy
Tanner Tech
Afrotechmods
Applied Science
Gerry Sweeney
Jeri Ellsworth
mjlorton
The Signal Path
w2aew

You have seem to have missed Big Clive and AVE from the list

 

[phaZed]

AVE more for chuckles and metal pron, with his CNC that's to drool over. Big Clive fits the bill, check out his new coffee mug lol..

 

[Stever]

AVE more for chuckles and metal pron, with his CNC that's to drool over. Big Clive fits the bill, check out his new coffee mug lol..

At work I deal with the same as AVE's CNC, we have the same and bigger
We also make test equipment for Tetra pak stuff, one of the head honcho's there used to be the chief engineer on the Royal Yacht Britannia !
Big Clive is the proud owner of one of the 3 known youtube AVE hammers, Dave at EEVblog and Adam Savage of Mythbusters being the others !

Edit, AVE's CNC appears to be of a vintage ( not very old ),that still has a floppy drive for loading programs as well as the standard RS232 port

 

[alex777]

It's not just the power on sequence !
Modern motherboards may have a ridiculous number of layers internaly with blind buried via's, not just what you can see on the top and bottom !
Typical track widths can be .005" or less for internal layers and BGA, if you have a cracked internal track or via then there is nothing that can be done about it !

I'm totally agree with you, and that is where I'd like to be able to diagnose that problem you mentioned as an example.

 

[Stever]

I'm totally agree with you, and that is where I'd like to be able to diagnose that problem you mentioned as an example.

With motherboards its either a case of replacing the obvious or reflowing the whole board, then give up and source a replacement.
There is nothing to be learned from spending hours working with pcb tracks that you cannot see and components that require a 3D microscope to see and are either un identifiable or unobtainable !

 

[Larry Sabo]

I'd like to understand power on secuence of motherboards, so I can diagnose them and fix them properly for repairing. Where do I have to start studying? Any suggestions, guys? Books for reading or something else?

This video on Adamant IT's YouTube channel talks about the power up sequence and how to diagnose power problems. It's for laptop motherboards but the techniques apply to desktop MBs as well. I assume you have studied electronics enough to know diagnostic techniques for the various MB components.