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It was working fine then the display got glitchy.
So I booted into single mode and typed the nvram gpu-power-prefs code and it worked. Now I'm wondering if the GPU died…
But then again I remember seeing a Louis’ video about bad soldering on 2012 models but I think it was the Retina one. Does the non-Retinas have bad soldering too and if so does the symptom look like it does in this picture…?
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So I warmed it up the board to remove the silicone around the GPU and applied some flux.
Then I covered the surrounding components with tinfoil but honestly don’t know if it helps or not. I did it just in the sense that it can’t do any harm so why not...
Then I used the hot air gun at 300C for 5min timed. And waited till it cooled down to clean up with isopropyl alcohol.
A ultrasonic bath would be ideal but I don’t have that so iso it is.
Then I assembled it back and... here it goes:
It worked! :D
Even after hours on a stress test still wouldn't go above 70C
I did do a few ‘improvements’ to ensure lower temps though: not only I used high performance thermal paste but I also used some copper shims sandwiched between thermal pads on the back of the board transferring some of the heat to the aluminium bottom plate and essentially turning it into a heatspreader.
Word of caution though: this GPU comes covered with some sort of tape or whatever and it can be very difficult to remove.
I knocked off a resistor and had to spend quite some time soldering it back on…
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The 2012 Nvidia GPU's are much better than what the 2011 models had. I mostly see 2011 systems with bad GPU's as the owners tend to push them beyond what they can handle and the systems cooling is just not that great if your pushing the system hard.
Carlos - Clearly you got a bad one and I'm impressed on your efforts! Just like what I would have done! Good job!
Thanks Dan! :D
Actually my first 'patient' was indeed a crippled 2011 - it is known to be bad to how much worse could I make it right?
But it worked! Same method described here difference being I only ran the stress test for about 2h and it did reached 90C a few times so I stopped - didn't feel like pushing my luck too much :P
UPDATE: done a couple 2012/Nvidia and a couple 2011/AMD.
100% success with the 2011/AMD and 100% failure with the 2012/Nvidia.
But I think maybe the issue was more of power user vs casual user: the 2012/Nvidia were being used for daily video editing and the 2011/AMD were from people who might do some light home video editing but will most likely use it for social media and the like.
So my conclusion would be: if the user profile is of a power user better tell them to buy another and sell the faulty one with the GPU disabled. But if the user profile is of a casual user then it might be worth giving it a try :)
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Carlos Ferrari totall y agree with @arbaman on the 2011 is absolutely commonly caused by the GPU chip itself. The processor is a flip chip design and the issue is commonly caused by the solder bumps between the IC and the substrate. The key to this is the design of the processor which is a flip chip design. The proper definition of that can be found at Wikipedia "is a method for interconnecting semiconductor devices, such as IC chips and microelectromechanical systems (MEMS), to external circuitry with solder bumps that have been deposited onto the chip pads." So what happens is that the chip heats up (due to poor design of the ventilation and heatsinks. It does not matter if it is a MBP a PS3 or a XBox) and the bumps that connect the chip to the substrate lose contact and your chip (in this case processor) fails.
As you can see the "bumps" are what actually connects the die to the substrate to make the chip complete. If these bumps fail, the die does no longer make contact with the substrate and thus no contact with the circuit board. The chip has failed.
Here you can see the space where the bump has failed and no longer makes contact. We are talking microns of space here.
Sometimes a bit of pressure on the top of the die potentially close the gap. Same with a reflow, which may allow some of material from the bump to reshape and starting to make contact again. The heating of cooling of the chip during use is what will eventually cause it to fail again.
If you are going to do a reflow then the general guidelines for a good profile would be something like this:
Temperature ramp up 1ºC/second
Peak temperature should be 200C to 210C
Remain above liquidus (183C) for 45-75seconds
Do not heat any packages above 220C since this will most likely destroy the IC
Here is a good document that will help you with the profile as well. BGA-Reflow-Rework.pdf
This is not an answer just a quick and dirty explanation of what has commonly affected the flip chip designed GPU
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Yep that pretty much describes the plan I have in mind except I thought about 250C as that's what I saw online...
Also one thing that people seem to forget is to remove those silicone bits around the die as it will probably prevent the die from getting a proper reflow.
And sure reaballing with leaded solder would probably be ideal but we're talking about a 7 years old laptop here… A bit of elbow grease to have it going is fine but a expensive job that might cost as much as the laptop itself is something else…
I'll post pictures once I get it done - wether it works or not :P
Carlos, what you saw online is a pretty useless reflow of the entire GPU to the board soldering, which hasn't to be mistaken with the pictures provided here that show the inner structure of the GPU, which can't be obviously taken apart, to explain why a reball or a reflow are a waste of time or a temporary side effect of the IC warming up. If you're doing it on your own to try to extend your Mac life a bit that's fine, but it's not a repair and should be deprecated as a permanent solution as it isn't. The temperature @oldturkey03 mentioned refers to the chip core, which you can't determine nor measure unless you run a soldering tunnel to earn your daily bread.
Thanks for the pics @oldturkey03 , they're worth more than thousand words :)
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Sometimes it shows different patterns, everything gets pink or green with shadows, other times it doesn’t show anything at all, but unfortunately yes, your Mac picture definitely looks like a faulty Gpu, bad luck. The 2012 release didn’t show such an epidemic like the 2011 models, but still a Gpu may go bad especially if used under heavy loads, videogames, or if the machine has never been cleaned on the inside. The higher the temperature it reaches for longer time spans the higher the risk a Gpu gets fried.
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So if it was a chip with bad soldering the display wouldn't show like that…?
Well, it's not a bad soldering of the Gpu to the logic board as somebody believes, the fault is inside the chip, where you have parts soldered to each other and then incapsulated in the Gpu as we see it.
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Let me correct @arbaman - answer a bit.
Arberman is correct the 2011 models have a bad GPU and/or the VRAM chips. The issue is in fact the soldering which can be either the chips external connections or it can be the joints within the chip (FlipChip).
Apple’s push for lead-free solder while noble got them into trouble. As the volume of Tin increases in the solder, the Tin can create whiskers! This is when the tin migrates material to an apposing charge (NASA - What are Tin Whiskers). This can happen within either solder join area. It is believed excessive heat aggravates this process.
The 2011 GPU’s had this failure internally as the chip ran hotter and Apple failed to cool the GPU effectively. So using a Lead containing solder removed the Tin whiskers risk as well as solder breakdown (cold solder joints) which is also present. While we can clean off the old solder and apply Leaded solder around the external joints we just can’t get into the chip to fix the Flip-Chip joints. Its suspected NVIDEA was smart enough to add a bit of lead into the solder (or used a better formulation) they used within the chip so the issue is not present within their chips.
We are also to blame here as well!
We forget the design of a given system was based on the technology it was build with, not for the applications we desire to run on it today, which can push the system to the breaking point.
A 1950 Packard Super 8 was a great car in its day, its top speed was about 85 MPH. But, if you pushed it over 60 MPH for long periods you would kill the engine! In the day the roads where still mostly dirt or gravel other than the cities which were mostly cobblestone and tar. Roads that you could maybe travel at best 50 MPH.
Within 20 short years the interstates and most major roads where rebuilt into modern roads we have today able to support cars running 85 MPH or faster as the top speed most limited to 65 MPH. So going 60 in the old 1950 Packard would quickly kill the engine as the road was just too much for it. We of course don’t blame the car as it did what it was designed to run at, the roads just got better!
So what does this have to do with the MacBook Pro’s? Basically, the same! The applications we run on these systems have just like the roads gotten better but in doing so we are expecting the system to keep up running these apps without failing us. Of course that is the same as the old Packard expecting it to work beyond what it was designed to run at. So running heavy graphics will kill your system over time.
Is this fault present in the 2012 model as well? Yes, it is! just not as badly! The newer NVIDIA GeForce GT 650M GPU ran more efficiently from the AMD Radeon HD 6750M or 6770M GPU’s used in the 2011 models so it didn’t struggle as hard so the systems GPU ran cooler.
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Meaning what, the GT650M damage is more likely to be outside and possibly fixable or is it more likely to be really dead?
BTW: the issue I mentioned Louis' videos show is not the GPU chip but the power buck converter that gets loose because the soldering is crap and I was wondering if I've got the same issue here… It would be much easier if it were this:
The GT650M is just a better designed GPU! Going back to the car analogy, think a 1960's car still not as good as todays car design. Technology is not stating still! Newer chips run cooler as the Node Process has improved. Each generation can either take the same chip design to a lower power design (heat) or allow a more complex process run at the same power level.
Your issue is not a messed up buck converter (solder or damaged). It that where the case you wouldn't have an image at all or it would freeze up. You also don't have a retina model which is a different design.
Your issue is clearly a GPU/VRAM issue. As I stated bad solder is likely here. Reballing the GPU and the four VRAM chips is what I would do. Basically pulling off the chips cleaning off the solder and then using better solder. This is not a DIY type of job as you can also damage the board trying to fix it.
I usually use a smartphone analogy as it is easier for non-tech-savvy to understand so I would say it's the same as having a iPhone 4 and trying to run iOS12 with the latest apps - it might 'work' but it won't be ideal.
My explanation however does not imply hardware failure due to that usage but most of the times it conveys the message in less time explaining…
And yes even though both are 2012 the Retina is clearly a new design whereas the non-retina has pretty much the same design from 2008/09.
But still both were produced at the same year so the same soldering issue is not that far-fetched. But you're right if it were the buck converter the symptoms would be different so it must be GPU/VRAM :(
So what I'll try to do is to reflow the GPU…
(Yeah it's a Band-Aid fix and all that but the alternative would be to disable it and use the integrated but I can do it if the fix doesn't work anyways. And learning is worth a shot in my point of view)
I guess I'm showing my age, my uncle had a Packard when I was a kid (I was 5 at the time), driving us up to Boston from New York overheating a few times as he was pushing it hard to get to my Aunts wedding,
I still have an old rotory phone on my desk, but have an iPhone in my pocket ;-}
You're probably older than me but I'm no spring chicken either - over my 40s already lol
I do try to keep up with the people I have to deal with though otherwise I'll soon be the old timer screaming at kids to get out of my lawn haha :P
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Where is the GPU located on a mid-2012 MacBook Air
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