A:AnswerIt can use AHCI or ATA. In your case, just select ATA on the bios.
I would also enable Legacy mode if you have one. Set secure boot to "disable".
A:AnswerYou might have to purchase specialty screw driver, but it is fairly simple plug and play, make sure you transfer any adapters attached to original hard drive.
A:AnswerYes it is. I've replaced the HDD in all my desktops with this SSD and it works and performs great. For mass storage, I also use an internal 1TB HDD data an the Sandisk SSD for the OS and programs.