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The ZIF connectors for those fans aren't different or much more fragile than the ones in most other laptops.
The adhesives on certain cables tend to trip people up a bit with causing them to pull more than they should and damage things.
Gently working under and releasing the adhesives on those fan cables with the spudger (or a fingernail) before you even start trying to move/unplug them will work a lot better for not tearing things than grabbing them with tweezers will.
The TouchID cable is fragile. Still shouldn't be any serious risk of breaking if you know to treat it with caution, but that would always be the one to take the most care with and watch the most closely while you're working around it.
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The secondary challenge is pretty much just making sure you have all the cables out of the way when you're putting the board back in, because you've got a dozen or more that you need to watch the positioning of and/or tape out of the way.
The actual issue I have with phones isn't that the connectors/cables break apart if you look at them funny, it's actually the god damn screens are insane to deal with and replace, with all of that adhesive crap.
This all to say, I think Apple is doing poorly here, their ribbon cables should probably be more robust on these often quite expensive devices. I know they can do it because I've experienced Apple devices with pretty robust internals... (and also similarly, have seen and heard of Apple devices where they've mysteriously cheaped out on components like voltage regulators and made their devices totally unnecessarily worse and more failure prone.)
Switched to a P50 with twice as much RAM, and that's just one socket of four. Since upgraded to the max, with bigger SSD, it's still a beast.
Compare with Apple's use of glue and special screws, when Lenovo provides detailed service manuals on its web site.
What I've done so far:
* Maxed out the RAM to 16GB (using lower voltage DIMMs to increase battery life)
* Swapped to a larger 9 cell battery
* Upgraded the CPU (and thermal paste) from a 2 core/4 thread i5 to a 4 core/8 thread i7
* Flashed a custom BIOS to remove the WiFi card whitelist and installed an Intel 7260 WiFi AC + Bluetooth card
* Replaced the stock 1600x900 TN panel with a 1920x1080 IPS display
* Replaced the barrel charging port with a USB-C connector (requires a 20v USB PD power supply, but those aren't super rare or expensive)
* Replaced the HDD with an SSD
* Replaced the optical drive and a 2.5" drive enclosure and installed a second SSD
Future projects:
* Flash Coreboot
* Upgrade to a faster i7
* Upgrade to a 1440p IPS panel
* Swap to a T420 keyboard
I've never had any feeling that anything is going to break. Certainly not any of the cables or connectors.
I had worked on desktop computers before, but never done anything more complex than changing RAM on a laptop.
I have had trouble in the past because of this, usually not with small electronics. I busted a 4-pin Molex in a computer trying to plug it in with the pins not lined up quite right. It does require a decent bit of force, but accidentally breaking things is not uncommon for me because I just can't tell when I'm going too far. Same with screws, I pretty much always overtorque screws if I do it by hand.