Panasonic CF-20

[Maxpower3]

Hello everyone,
I'll come back with that. I started here but it wasn't the right place
because it's not a bios or password problem

https://www.badcaps.net/forum/troubl...87#post1866387

blackscreen, no boot, no backlight after save and exit in bios setup.
just led power on/off react

I have tried several bios here, none have worked so far

I think it's dead, even the USB key died at the same time as the computer.
Just the lights power and beep when it turns off

News:
I noticed that the motherboard boots when the screen is unplugged.
If I connect HDMI or LCD, the motherboard no longer triggers any reaction.
On the other hand, if I unplug the screen and the HDMI, the keyboard responds with caps lock and activity on usb key.

The backlight works if I force it. Pwm LED 0v and enable 3.3v LED.
I don't think the screen has a problem


I think I should look into display management around the PS8407A or CPU
what do you think?

Are there any diagrams?
Thanks

edit: PS8407A /1629B/ wg1219lm remplaced same
if I connect after boot HDMI, it does not restart after a ctrl alt del

[Maxpower3]

I had two cards that didn't work

the first mentioned above and another that did nothing just consumption and no reaction.
I exchanged several components to see the reactions?

Now, both cards work,
I noticed a lack of solder on 2 chips and I reflowed this area.


the first time, I thought it was heating up the processor and I was lucky thanks to the reflow.
but did not last.
so I have reflow only it's 2 chips.


The 1st card worked again (the one that did nothing)
I then on the 2nd (starts only without screen).
it also works again now!

Is this a stroke of luck or will it hold?? to see over time