Acer Aspire 6920G reboots on AC Adapter

[lagouzas]

Hello everybody,

This is my first thread in this forum, I hope I'll be lucky.
I 've run into this problem for 4th or 5th time with no success.
Laptop model is Acer Aspire 6920G and although it works fine on battery, when ac adapter is plugged in it, randomly crashes and reboots.
Battery is checked to be ok, different power adapters have been used, the power jack checked to be ok, different CPUs have been used, but no solution.
I am definately sure that it's a common motherboard failure for this model. Some claim that it's a faulty Sata controller, others that there are 2-3 bad caps near the CPU socket.
The standard fact is that when laptop takes more current than it takes when on battery, it crashes down and reboots. No matter what OS is installed from Linux, to windows XP or Windows 7, it's not a driver problem, but a hardware problem. Any idea wourld be appreciated.

[RJARRRPCGP]

Re: Acer Aspire 6920G reboots on AC Adapter

Sounds like it's loosing power when loaded enough for it to turn off.

[lti]

Re: Acer Aspire 6920G reboots on AC Adapter

I don't know why a bad SATA controller would allow it to run normally on battery. This seems similar to the problem caused by bad caps in Toshiba laptops.

[lagouzas]

Re: Acer Aspire 6920G reboots on AC Adapter

After some research, I think that you are right lti. This model has the same cap for regulating power consumption, as Toshiba A300 has, with the same problem. I have ordered it, and I am about to change it next week. Hope it will do my job.

[c_hegge]

Re: Acer Aspire 6920G reboots on AC Adapter

Moved to Troubleshooting Laptops and Notebooks. This kind of thread isn't for the FAQ.

[rievax_60]

Re: Acer Aspire 6920G reboots on AC Adapter

After some research, I think that you are right lti. This model has the same cap for regulating power consumption, as Toshiba A300 has, with the same problem. I have ordered it, and I am about to change it next week. Hope it will do my job.

Replacing it with the same type of capacitor usually results in near term failure.
This thread, https://www.badcaps.net/forum/showthread.php?t=8991
has lots of useful experiences from other members.

[dj_ricoh]

Re: Acer Aspire 6920G reboots on AC Adapter

Disable the second core of the CPU in device manager when you run on battery then you connect the charger.
It won't reboot.

[dycc]

Re: Acer Aspire 6920G reboots on AC Adapter

same issue as toshiba L300 . replace NEC TOKIN cap by four tantalum cap (330microfarad)

[Francisco.s]

Re: Acer Aspire 6920G reboots on AC Adapter

After some research, I think that you are right lti. This model has the same cap for regulating power consumption, as Toshiba A300 has, with the same problem. I have ordered it, and I am about to change it next week. Hope it will do my job.

You can add a 1500 uF 6,3v in parallel (a good quality one (low esr)) and check its behaviour.

[lagouzas]

Re: Acer Aspire 6920G reboots on AC Adapter

Thank you everybody for your help.
Replacing NEC TOKIN cap, with a new one of the same kind fixed problem for me.

[rievax_60]

Re: Acer Aspire 6920G reboots on AC Adapter

Thank you everybody for your help.
Replacing NEC TOKIN cap, with a new one of the same kind fixed problem for me.

How did you stick the new one on without melting it?

[whaldsz]

Re: Acer Aspire 6920G reboots on AC Adapter

he probably used a bga rework machine.

[ghojariya abdul]

Re: Acer Aspire 6920G reboots on AC Adapter

its tokin capasiitor prob. put 4 330uf capasitor .