820-2915-B Distorted image

[javier_herart]

Hello,

I dissabled the GPU with 2dude method on this one like 5 months ago.

Now came back with distorted image after entering password (when loading OS and on welcome screen looks ok) and beeps 3 times...

I tried wieht different ram sticks on both slots and same, tried doing some preassure on the ram but same...

Any help?


Thanks!!!

 

[2informaticos]

Should be a problem with iGPU.
Appears only when macOS tries to load its driver.

You can try a test with ASD OS version.

 

[javier_herart]

I am struggling to get the correct ASD OS, some more comments:

1. When entering boot menu, the image on the screen distorted once and the computer restarted (just like when I entered the password to enter the user). Could this change the assumption of the faulty IGPU?

2. I got the ASD OS 3S148, but its been loading for 20 minutes and nothing happen (apple logo with loading circle).
This is the a MacBook Pro (15-inch, Late 2011) built in the second half of 2011 with 2915 board. Is that the correct ASD?


3. I am seriosly considering replacing the CPU on this, good possibily of the being the a CPU issue?


Thanks

 

[2informaticos]

iGPU and RAM are strongly related.
You may have only DDR slots problem.

 

[javier_herart]

Hello

I can confirm now that the issue is also when loading the SO and/or in boot menu BUT I noticed that the issue is only with battery connected!

I will try another battery and let you know, in the mean time, any comment/suggestion on this one?

 

[2informaticos]

I saw 2915 boards which only works good with ORIGINAL battery.
Several peoples on Internet complain about aftermarket batteries.

 

[javier_herart]

I tested with 2 original, status: Normal batteries and same issue...

Any suggestion?

Is there any voltage/signal related to the RAM that could be changing with and without battery?

 

[2informaticos]

CPU working frequency is adjusted, depending if battery is present, or not.
The battery can supply peak current, if the power from charger is not sufficient; when CPU enters turbo boost mode, for example.

 

[javier_herart]

I checked with osciloscope all voltages big coils and I couldnt notice anything between no battery and with battery (specifically when image distorted).
would you recomend change charger, mosfets or something?

(At this moment I think this is only for study since I think I will order a Replacement one for the customer later today)

 

[javier_herart]

Any suggestion?

 

[2informaticos]

When disabled GPU, did you remove the two resistors from the GPU power supply?
At least one should be removed.

Try to test with 3S144 ASD OS...