My Supermicro X8DT3-LN4F motherboard supports SAS. The cheapest price per gigabyte I can get at 7200RPM is for an 8TB SAS3 drive. I have searched and it appears that SAS2 is backwards compatible with SAS 1 (Are 6Gb/s SAS drives compatible with 3Gb/s SAS interfaces?), and it appears SAS3 is backwards compatible with SAS2, but I have not yet seen any confirmation that SAS3 is backwards compatible all the way back to SAS 1. With the right cable, would such a drive be compatible with an older SAS controller like in my motherboard, in the way that USB 3.0 can work with USB 1.0? Or would it be more like LTO drives, where the backwards compatibility only goes back a limited amount? And if these are not compatible, why not?