Hi there. I have a late 2013 imac still under warranty so i don't want to open it up and change drives. I am running el capitan and have an internal 1tb hdd and i have an external 128gb ssd (connected via an external usb 3.0 uasp caddy). My current system in the internal hdd involves a: system partition 830gb "hybrid" Second partition that has osx and basic apps on for maintenance, like a recovery drive but with desktop functionality etc - 40gb "imac rescue drive" A Windows partition (yet to install Windows 10 into) - 130gb "Windows" I tried installing isx to the ssd and then migrating accounts to it (and then moving large files /folders to the hdd and making symbolic links to them) but didn't get a far as the system loading back up once i had migrated any data. Both times u tried to do this osx bit process froze on the progress bar (about the quarters of way the first time and half the second time i tried doing this). So i just don't know what was going on there (i am fairly certain the first time was because there was no room left on the ssd (164mb?) to boot properly but the second time i only migrated a small enough amount of data to keep enough free space on all to be able to boot up again). I don't to keep messing about trying to get crap done i just want my system back preferably booting off ssd. I have looked into making a diy fusion drive since and like the idea. My question is should i (1) somehow set my system up, like initially trying to, with the system booting off the ssd and data moved and linked to the hdd or (2) setup a fusion drive and restore my time machine backup to it? If it's number 2 is there a way that i can tell core storage not to try and move certain files to the ssd/to keep make sure certain files remain on the hdd (ie; large media folders and files etc)? This is my time machine backup of my setup : Accounts - Admin 9.44gb Ruth 339.1mb Steve 88.66gb Work 6.82gb Computer and network settings 1.7mb Applications 106.65gb Other files and folders (includes alot of my media and docs that i have in the shared user folder basically) 479.15gb As you can hopefully see i have a problem if i am to migrate, move (to hdd) and then symbolically link (to ssd) user accounts, applications and other media data due to sizes and the tiny size of my ssd. I am under the impression i can do this but in sizeable chunks but, as i said previously, i have tried twice and it just doesn't seem to work Please can anyone give me advice and a step by step guide in how to do this?