2022-05-22
tl;dr I picked up the stubby Sintech Apple to M.2 adapter and a 960GB Corsair MP510 and it's been great - no issues installing/running, thermally good, no noticeable extra power draw.
Last year I picked up a used 2015 Macbook Air 7,2 to use as my primary laptop. I wanted something with decent battery life and good touchpad without being too expensive, and it fit the bill nicely. It's no powerhouse, but perfectly adequate for some programming projects, light gaming and all the other bits and bobs I want to use a laptop for (it would be nice to be able to run newer games but that's what my PC is for).
So far it has been really good, however its main limiting factor was the 128GB SSD it came with. I've started dabbling with Flutter, and that needs a lot of space (XCode is huge, Android Studio plus the SDK is huge, Android emulators aren't small etc.). Not to mention that that's not all I wanted installed on this machine. I needed more space.
If you've ever looked at upgrading the hard drive in an Apple laptopc, you've probably stumbled upon this MacRumors thread. It's a trove of information containing more than you'd ever want to know on the topic. However that blessing is also a curse, and it makes it a little tricky to work out what is best. The key issue with finding the best option is that a lot of manufacturers have updated their existing SSDs to use different NAND chips (replaced TLC with QLC) which seem to be worse across the board (performance, power use, thermals), so previously recommended SSDs are implicitly no longer recommended, even though they tend to use the same model numbers.
Due to the proprietary connection used by the SSD in the laptop, you need two things: a proprietary connection to M.2 adapter, and a normal M.2 SSD. The post above recommends only using Sintech Apple to M.2 adapaters, so that's what I did (I bought the stubby one, not the full-length one and it's fine). The other thing is the SSD. I chose a 960GB Corsair MP510 because a) it still uses TLC chips, b) doesn't seem to have any issues as far as that thread goes and c) I've always had good experiences with Corsair products in the past (with the exception of their first-generation H100i AIO CPU coolers years ago - noisy and not particularly good performance - I'll stick to air, thanks).
Installation was easy, following the iFixit guide, requiring only a T5 torx bit, P5 pentalobe bit and about 15 minutes.
Once installed it's a case of booting into recovery (hold down CMD+R or Option while booting), initialising the disk in Disk Utility and then installing the OS. No extra kexts or anything required, and everything works as it did before, but with way more space.
In daily use it feels exactly the same as the old SSD, and temperature and power draw don't seem to have been impacted at all. Out of interest, I ran the BlackMagic Speed Test before and after, and both read and write performance approximately doubled, though it isn't really perceptible to me in normal use.
Overall, I'm really happy with the upgrade (it feels the same as before, but has more space)!