As you have already mentioned there is a big difference between IDE and SATA. Most older computers and some newer computers still have IDE ports even if they are not being used. If a SATA port is available it should be utilized since its faster. There are 3 types of SATA: SATA I, SATA II, And SATA 6. The latter won't be seen much since only the fastest Solid state disk's are capable of using this speed efficiently. SATA I and SATA II are backwards and forwards compatible meaning a SATA I drive will operate on a M/B having SATA I or SATA II but it will operate at the slower speed. There is a hitch though with a few select motherboards "motherboard host controllers using the VIA and SIS chipsets VT8237, VT8237R, VT6420, VT6421L, SIS760, SIS964 found on the ECS 755-A2 manufactured in 2003, do not support SATA 3 Gbit/s drives. Additionally, these host controllers do not support SATA 3 Gbit/s optical disc drives."