5930G restarts when USB is inserted

[Nightwalker]

Hello everyone

Acer laptop, 5930G model, EIGER MB
schematic attached

Problem:
When AC adapter is present, laptop shuts off and restarts, a few seconds after a USB device is inserted(at windows). If a USB is present from the beginning,laptop entering windows and same thing happens after 10 seconds(shut off-restarts). If a usb device is NOT present, laptop working ok.
At battery mode no problem at all, with and without usb device present.

I dissasemble it and remove all usb powered devices and problem remains.
I give external 5V to usb device(cut internal 5V) and problem is the same.

EXTRA INFO:
If laptop is at AC mode, a shut down via windows or via power button acts like a restart.
With battery only, working right, shut down is a shut down.

Things already tried:
Final BIOS version
Different RAM modules, AC adapter,GPU and CPU, nothing change..
All temps are below 45C

Any ideas??

[stj]

Re: 5930G restarts when USB is inserted

internal lithium clock/ram battery checked?

[Nightwalker]

Re: 5930G restarts when USB is inserted

Hello stj, thanks for reply

Yes, already checked, forgot to mention it ;-)

[RJARRRPCGP]

Re: 5930G restarts when USB is inserted

Sounds like the Windows kernel panicking...

[Nightwalker]

Re: 5930G restarts when USB is inserted

Hey RJARRRPCGP

Interesting approach..
If so, why this doesn't happen in battery mode also?? Different power settings?
Maybe i'll give a try with a live cd to see what happens

[highpulse]

Re: 5930G restarts when USB is inserted

nightwalker , f this is happening with dc power is problem on 19 volts line . if there is not a 19 volts line arriving to certainn components while the charger IC says its DC connected , that it might not have enough LDO power to suplly usb's making is to kernel panik . meanwhile in battery system now that power is less .. so therefore it wont be a problem . so first thing to chek is the integrity of the 19 volts line .

[Djosla]

Re: 5930G restarts when USB is inserted

I belive that board has nec tokin capacitor...change it and it will solve your problem...

[dmartins]

Re: 5930G restarts when USB is inserted

@Djosla is right , some months ago i change nec tokin in a 5930G and the computer is now OK.

and the problem was +/- the same

[Nightwalker]

Re: 5930G restarts when USB is inserted

Thanks everyone for your help and support, deeply appreciate it!!

Just replace the tolkin cap as you suggested with 4x330 tantalum and problem seems SOLVED!
Still cannot believe that a cap @VCC_CORE leads to that kind of problem...
Besides that, now a shutdown command works as it should be!

Thanks again guys!!

[dmartins]

Re: 5930G restarts when USB is inserted

happy for another computer working!

[Djosla]

Re: 5930G restarts when USB is inserted

yeap no problem...