A n00b needs your help - Macbook pro 17" mid2010 820-2849-A

[jultsu]

I have a 820-2849-A which has the following symptoms:

Screen output is cut in half, the left side being on the right and the right side on the left, with a black void in the middle. Pictured is the Apple Hardware test running from a USB stick:



Problem is not with C9560, it is holding a nice 1.845v against the ground from the moment the board powers on.

Trying to boot to macOS hard crashes and computer restarts.

I used to be able to disable the Nvidia GPU by EFI shell commands, which would restore the screen back to normal and I could boot to macOS and use the computer, but this is not working anymore after a 6 month hiatus from using this machine.


Would anyone recognize this issue and be able to tell is the GPU fked or can this be salvaged somehow, and point in the direction what to check next?

thanks.

[jultsu]

Re: A n00b needs your help - Macbook pro 17" mid2010 820-2849-A

So... after heatgunning very gently the general area of the C9560 the screen output did return back to normal. So I'm guessing its still the poly cap which is causing these issues?

[piernov]

Re: A n00b needs your help - Macbook pro 17" mid2010 820-2849-A

Usually C9560 doesn't die on 2849, but you can try to replace it anyway. I don't have high hopes though, the issue will probably show up again.

[jultsu]

Re: A n00b needs your help - Macbook pro 17" mid2010 820-2849-A

The split screen issue returned with a hard freeze after one hour of Youtube playback / 3d benchmarking with the Nvidia chip enabled.
I might try to concentrate the heat output purely just to the single cap somehow to try and isolate the issue even further.

Is there any other poly cap that i should be looking at, since the issue most likely isn't with the GPU or the VRAM chips?

[jultsu]

Re: A n00b needs your help - Macbook pro 17" mid2010 820-2849-A

Well, replaced the c9560 with a 6.3v 220uF "C" sized poly cap, no help. Still boots mostly with the broken graphics, sometimes the picture is ok again. Heatgunning the c9560 area doesn't seem to help anymore as well. Would this mean that the GPU has had it?

[KvnTM]

Re: A n00b needs your help - Macbook pro 17" mid2010 820-2849-A

Well, replaced the c9560 with a 6.3v 220uF "C" sized poly cap, no help. Still boots mostly with the broken graphics, sometimes the picture is ok again. Heatgunning the c9560 area doesn't seem to help anymore as well. Would this mean that the GPU has had it?

Heat the GPU to 100°C. The GPU is failing if it works after that.
But i doubt that the chip will be dead. It looks like a framebuffer issue. A dead GPU usually creates lines, a distorted or garbled screen.

Give the vram chips a mild reflow with lots of flux.

Are there no weird artifacts and is everything displayed correctly ignoring the split screen?

[jultsu]

Re: A n00b needs your help - Macbook pro 17" mid2010 820-2849-A

Well, now that applied some alcohol (fairly liberally) to the board around U5340, I started getting some distortion in the picture. This hasn't happened before.



U5340 because I tried hunting for GFXIMVP_ISNS_IOUT voltage (found something in Rossmangroup's website: https://boards.rossmanngroup.com/for...n-no-backlight) and I also get about 0.02v on R5379, would this give any clues?


Unfortunately reflowing VRAM chips goes way beyond my skills and equipment, a single component with a few pads/legs might be still doable.

thanks anyways for the help

[KvnTM]

Re: A n00b needs your help - Macbook pro 17" mid2010 820-2849-A

Well, now that applied some alcohol (fairly liberally) to the board around U5340, I started getting some distortion in the picture. This hasn't happened before.



U5340 because I tried hunting for GFXIMVP_ISNS_IOUT voltage (found something in Rossmangroup's website: https://boards.rossmanngroup.com/for...n-no-backlight) and I also get about 0.02v on R5379, would this give any clues?


Unfortunately reflowing VRAM chips goes way beyond my skills and equipment, a single component with a few pads/legs might be still doable.

thanks anyways for the help

Hm this looks like a dying gpu. Just heat it up once while unpowered! 100 - 120C is enough. This doesn't look like a power supply issue.

[jultsu]

Re: A n00b needs your help - Macbook pro 17" mid2010 820-2849-A

Hm this looks like a dying gpu. Just heat it up once while unpowered! 100 - 120C is enough. This doesn't look like a power supply issue.

Thanks, will try that later. There is some browning around the VRAM chips' glue, this board has probably been heatgunned around that area earlier

[jultsu]

Re: A n00b needs your help - Macbook pro 17" mid2010 820-2849-A

Hmm okay.

Heatgunned the GPU - no difference.

Heatgunned the VRAM chips - no difference. Still tiny amounts of artifacting.

[Audio Aesthetics]

well wtf man what happened....lol I have the same board and she runs great fast as hell even in 2024 but when she gets super hot she shuts her screen off and then I have to restart! did you scrap the board or did you fix it??