820-2915 no chime,

[Repairable]

820-2915

No chime, black screen,

But i have green light and fan spin
System is brainless like louis says, meaning no vcore

please dont tell the direct answer, but just kick me in the right direction


Ppbus_g3h 12.56v
PPVIN_S5_HS_COMPUTING_ISNS 12.56v
PPVIN_S5_HS_GPU_ISNS 12.56v
PPVIN_S5_HS_OTHER_ISNS 12.56v
PPDCIN_G3H 18.72v
PP3V42_G3H 3.46v
PPVRTC_G3H 3.3v
PP5V_S5 5v
PP5V_SUS 4.99v
PP5V_S3 5v
PP5V_S0 5v
PP3V3_S4 3.336v
PP3V3_SUS 3.3v
PP3V3_S5 3.3v
PP3V3_S3 3.3v
PP3V3_S0 3.3v
Skipping T29 rails,
PP1V8_S0 1.79v
PP1V8_S0_CPU_VCCPLL_R 1.784v
PP1V5_S3 1.5v
PP1V5_S3RS0_CPUDDR 1.5v
PP1V5_S0 1.51v
PPVTTDDR_S3 0.75v
PP0V75_S0_DDRVTT 0.75v
PP1V2_S0 1.21v
PP1V05_SUS 1.032v
PP1V05_S0 1.043v
Skipped backlight, no screen attached atm, and also no chime.

PP3V3_ENET 3.3v
PP1V2_ENET 1.2v
PP3V3_S0GPU 3.3v
PP1V8_GPUIFPX 1.7v at moment of probing 0v resistance 0.282
PP1V8_S0GPU_ISNS 1.78v
PP1V5_GPU_REG 1.5v
PP1V5_S0GPU_ISNS 1.5v
PP1V0_S0GPU 1.01v
PP1V0_S0GPU_ISNS 1.00v
Finaly vcore. Here is where the trouble should begin, according to Louis. I don’t know why lets hope I find out in the future
PPVCORE_GPU 1.11v
PPVCORE_S0_CPU 1.15v
PPVCORE_S0_AXG 0v Alarm bel....
(measured resistance but it’s the same as ppvcore_so_cpu 0.0002, but there comes 1.15v here nothing)
Oke going back to the pdf,
no stuff on R1370
no stuff on R1366
ok now I see this is out going lines not in, this means imo this only turns on after cpu turns on, damn

see attached picture for my thought on this.



Oke after going true the pdf again, I come across AXG PHASE that seems to create PPVCORE_S0_AXG
0.000v on both sides of L7550
PPVIN_S5_HS_COMPUTING_ISNS is present checked that before
Pin 1 12,56v 0.408
Pin 2 0v 0.408
Pin 3 0v 0.0003
Pin 4 0v 0.466
Pin 5 0v 0.0002
Pin 6 0v 0.0002
Pin 7 0v 0.00002
Pin 8 gnd
R7556 4.76v
R7555 0.003v 0.648 on rail


Lost completely.
Going true the pdf, I found cpuvcore enable, damn stupid.
All_sys_pwrgd 3.356v
CPUIMVP_VR_ON 3.356v
PM_PECI_PWRGD 3.356v

 

[dukefawks]

First heat up the GPU and see if it lives again. Then of course replace it.
Or just take it to Apple and whine long enough until they fix it under the extended warranty for this model.

 

[Repairable]

First heat up the GPU and see if it lives again. Then of course replace it.
Or just take it to Apple and whine long enough until they fix it under the extended warranty for this model.

Wil that work if the machine has been openend?
i have 2 that are stil in the program... sounds good

 

[dukefawks]

There is a difference between opened and fucked with, which are yours?

 

[Repairable]

1 is fucked whit it had damage on the lcd connector (so thats a no go) the other i dont know if it is prefucked.
just had the machine riped out the board and started measuring.

and replacing the GPU its only possible whit a bga machine?
and are they even possible to get? (good ones that is)

 

[dukefawks]

If you have to ask if you need a BGA machine, I already know this is not going to happen. GPUs are not hard to source, someone who can correctly solder them is a lot harder.

 

[Repairable]

If someone tells you you cant, show them you can ?

I asked because i think it is horsenshit that only a €9000,- machine can do that, and i thought if someone had done that before by hand it is you or Louis.

Now i need a big ass nizzle for my auyue station ?

 

[larossmann]

I find it to be the opposite. I can never find chips that aren't pieces of shit. To confirm that my process is not bullshit, I would go back and reball the chip I removed, put it back on, and now it went back to working the way it did before. It worked fucked up but at least it worked.. all those MCP79 I were buying had no video/chime, the MCP89 were just dead, the graphics chips were garbage. I'm done with that shit. If I am going to steal chips to put them on boards and waste a hour of time on it it'd better be chips I got for free, and stuff I can do in a few minutes or less. I find BGA rework to be a colossal waste of time.

If you're going to try soldering a GPU by hand you are going to fail really miserably. I am not saying that to encourage you to prove me wrong, I am saying that to keep you from wasting a fuckton of time on something that is fundamentally destined to fail. Even the people with years of experience who are highly capable would have issues doing that. If you don't have years of experience doing large chip BGA rework you will find it hard to do with the $9000 machine, much less a $100 aoyue.

Next board!