thanks - piernov post is amazing. I will study it with the board in front of me and report back 🙂

Cheers for now....

Thanks, I found the boardview!

I'll open the laptop and let you know - meanwhile, for my own education, can you tell me how that works? 19V comes in and...? I've got an ATX PC in mind where the PSU is generating 5VSB. But there is no such thing on a laptop so what is the power on sequence?

Thanks so far!

HI all,

I have an Asus S410U which is dead, no signs of life. The PSU is outputting 19V and it works when under load with an 8OHM resistor.

On the motherboard, I have 19V in getting into the first mosfet and then nothing. I don't see obvious shorts though I haven't checked with thermal camera. I noticed that the rail going to the RAM reads 4 Ohm but that might be normal.

First thing is: how does a laptop generate the "standby voltage"? I'd imagine the 19V is being stepped down into a lower voltage for the standby logic to work. Is there a controller...