when upgrading from HDD to SDD, are changes necessary in the setup of SATA (ATA, AHCI) and/or other changes?
Yes, there are a lot of changes that you should manage in order to get the best of your SSD. You can easily find good papers on the Web to do the job. At first AHCI mode becomes really relevant with SSD for queuing and processing commands and for some other features.
Here is a good shot in my opinion: [View:www.tomshardware.com/.../ssd-performance-tweak,2911.html:550:0]