Acer 5520 problem

[rtstorm]

Hi, i got this laptop it wont show picture on LCD and output VGA. Fan spin but then it rebooting loop. I check RAM, CPU. Then i did reflow. When reflow was over i try it and still the same issue. Then after 3-4 power on laptop show picture, and i head some weard noise near CPU. I see that someone has already repaired it with some shorting wire +3.3V

I noticed cap near the CPU, it has 1000uF but marking say 820uF. Voltages across him is 1.2V
Shoud i replace cap?

[lezsimply]

Re: Acer 5520 problem

Few years ago, I had acer 5520g no video output. At first I also replaced that cap with value from what schematic says but still same problem. I did a reflow on its dedicated graphics chip (8400go m) but no result.

Found out that nvidia chip located near processor socket needs to be reballed. But you can try replacing cap.

Regarding the jumper, mine has one too. but client said I'm the first one to open it up.

[rtstorm]

Re: Acer 5520 problem

i have only nVidia chip (MCP67MV-A2).

About jumper, i do not see why is there, on both ends is 3.3V cannot figred why but i will leave it there. I noticed that laptop worked without cap 820uF

[sorinac]

Re: Acer 5520 problem

Main problem on this types on notebook is the MCP67mv-a2. In most of the cases the chip malfunctions from the long time overhit. Try a reflow if not, then the chip is faulty.

[rtstorm]

Re: Acer 5520 problem

I did reflow, now it is working. At first i put thermal pad on it and temp was 75 C - 80 C. Then i use artic cooling mx-4 + copper plate now it is 55 C.

I think that the best way is to put new chip

[sorinac]

Re: Acer 5520 problem

also put the cooler on 5v to be allways on. Be aware that this chip don't have a long life left.

[Th3_uN1Qu3]

Re: Acer 5520 problem

Agree with the above. And you should leave that capacitor there.