I recently expanded the storage from a 256 Gb original SSD to 1 Tb Samsung 970 EVO Plus NVMe M.2 on a MacBook Pro 2015 15.6" running macOS Catalina 10.15.2 following this guide + and a specific guide for the SSD model I used.
I did it because I got tired of uninstalling large apps that I didn’t use often enough just to reinstall them when needed, constant notifications of low disk space, and scratch disks getting full when using the Adobe Creative Cloud apps (Photoshop, Illustrator, and AfterEffects).
This is not about getting more space on the SSD that is already inside your MacBook Pro (cleaning up the clutter). It is about replacing the drive altogether.
I’m documenting the process to help others that want or need to do the same.
Note that you are doing this at your own risk.
I used the following hardware for the switch:
- an 1 Tb Samsung 970 EVO Plus SSD
- this Sintech adapter
- 3 USB Flash Drives (1 x 256 Gb for backing everything up, 1 x 128 Gb for creating the macOS Catalina Bootable USB, 1 x 4 Gb for Etching the SSD firmware ISO onto the drive)
- a pair of T5 & P5 screwdrivers
The Flash Drives for the backup and the creation of the bootable USB are the best regarding speed I could find. For the SSD firmware upgrade, any stick will do.
Considering that I could use only half of the original drive because macOS was taking the other half, the storage increase was greater.
The steps I followed were the following:
- thoroughly documented what I had to do
- ordered all hardware (the SSD, the USB sticks, and the adapter + screwdrivers)
- created the backup of all my files on the 256 Gb stick
- downloaded the SSD firmware (an ISO) and etched it on the 4 Gb stick
- downloaded macOS Catalina and created the bootable USB with macOS on the 128 Gb stick
- unplugged the MacBook, unscrewed the back panel to open it
- disconnected the battery
- unscrewed the old SSD and pulled it out
- mounted the new SSD in the adapter and inside the laptop and screwed it in place
- connected the battery
- screwed the back panel back in
- plugged the MacBook to the charger
- started the laptop with the firmware stick in and updated the SSD firmware
- restarted with the bootable and the backup stick inserted in the 2 USB A ports available on the MacBook Pro 2015 model
- created the APFS partition on the 1 Tb SSD
- selected and restored the latest Time Machine backup ( for 220 Gb it took me ~1.5 h )
Details on the above steps, more pictures, and alternatives can be found in the articles I’ve mentioned in the beginning.
Currently, everything works great with a 3–4 times speed increase on writes and almost 1.5–2 times increase on reads.
My main issue was the storage and that is 4 times increased. Considering that I could use only half of the original drive because macOS was taking the other half, the storage increase was greater.
I was a bit concerned about the heat, as the laptop seemed a bit warmer on less stress than before. I noticed that after the first 12h the heat levels went down to normal.
I’m also searching for some enclosure to recycle the old SSD. Transcend has one, though you can’t buy it without an SSD. Their SSD, which is double in price, half the speed, and a bit less storage, comes with the advantage that doesn’t need an adapter and might run as the original SSD regarding heat, compatibility and the same performance.
You can keep the original SSD around to mount it back in if needed.