neurosis project has equipped me with various (mostly) 2008-vintage MacBooks. I’m a particular sucker for the 17″ ones. Two of them I paid $20 for, the other two were $34 and $50. Each one of them was sold for scrap as they were tested & reported as totally non-functional.
Most actually worked fine with nearly zero effort. One needed its RAM reseated. But two of them were really dead, that is to say, I could not get them to POST. As a person who builds the odd thing, when I look at a “broken” device, I think to myself: If I were gonna make one of those from scratch, this one’s like 99% done as-is.
Suffice to say, I got them all working and it was decently hardcore.
Of course I tried various things to get them working, but all I could get is the sleep light would turn-on after pressing the power button. I had two such units, 17″ models, a MacBookPro3,1 and a MacBookPro4,1.
I realized since I got these from the computer junkyard and they were already written-off as corpses, if I didn’t risk making them more dead, I’d probably never fix them at all. Nothing ventured, nothing gained, I suppose.
With basic faults ruled-out, the next thing to try was a reflow of the major components. Since the machines showed the slightest of life-signs, the CPUs became my main suspect, but I’ve had a GPU break its SMD welds before, so I decided to just reflow anything decently complex. I was considering diverting in to a project like this. But decided to cowboy it with my heat gun first.
To really get started, I had to first remove the logic boards and clean off the thermal paste/grease.
I already had a 1500W heat gun I got for using with heat-shrink. I blasted it against some raw solder to get a rough feel for what it takes for it to melt solder. The answer is not much.
While I had intended on reflowing the entire board, when I’ve seen youtube videos with similar projects, folks seem to often thermally mask-off a target chip. I figured this might reduce the air-flow pressure against the various tiny caps (etc), so I measured and cut a suitable shape in an Aluminum take-out tray.
I started blasting the heat to each major chip from kind of far back, about 350mm away. I watched adjacent solder pads, waiting until they looked a little shinier (I’ve noticed liquid solder tends to be be shiner). Overall, each chip probably saw a mere 20s of sustained heat, though at times I’d briefly get as close as about 80mm.
Once I felt like I’d delivered enough heat, I left the boards for a while to cool back to ambient.
During the reassembly I obviously had to apply new thermal paste. I’ve classically leaned towards the less-is-more camp when it comes to thermal paste, but then I watched this video:
While that doesn’t really land on an exact verdict, I then considered what they looked like when I disassembled the boards:
This seemed like a crazy amount of paste to me, but Apple tends to direct Foxconn rather well. I decided to split the difference between my classic amount and what was on there in the first place. The above video gave me the feeling like rounding-up slightly seems a bit less risky that rounding-down slightly. I put on a latex glove and used my finger to spread a thin layer evenly over the heat pads, then I added a little glob to the middle:
As it happens, the repair initially had no effect on one of the two machines. So I had to try it again. It did work the second time. On my way back in, I got to see how well my choice of paste application spread around, this is what I got:
I think that was precisely what I was aiming for, somewhat less than the factory, but clearly a notable quantity.
I used MG Chemicals 860 Thermal Transfer Compound. About a year ago I read this super detailed comparison of thermal compounds, MG’s 860 has A-grade performance and it’s inexpensive (perhaps due to zero marketing).
On both occasions the sleep light initially would only blink intermittently after the reflow. I thought I’d screwed my logic boards up at first, then released, like a champ, I’d left out my RAM. So, if you see that steady blinking white sleep light, it could be RAM.
The process worked. The machines went from nice-looking paper weights to being usable computers again. Granted these are pretty old, for ~$20 and some fun-time screwing around under the hood, I ended-up with some nice extra units to goof with. My previous post about Windows 10 on Vintage Macs would seem to apply.
This post was written from a machine with one of the repaired logic boards. 🙂
I’ve posted many pictures of this to a Flickr Album, here.