SATA actually seems like a step backwards in technology. IDE never was a very good technology, so being a step up from IDE isn't saying much.
For example, my main problem is described below from the SATA specs:
Connection Methodology
Ultra ATA – Master/Slave Shared Bus
Ultra ATA technology supports up to 2 drives per channel via a shared bus. Though the two attached devices are referred to as “master” and “slave”, there is no difference in operation between or priority given to the connected devices.
The host bus adapter is the true bus master and uses the master/slave status of the drives to route requests to the correct device and to determine the boot device. Though Ultra ATA supports a command queuing algorithm, it is rarely incorporated into devices, and thus the data bus is locked if a command to either drive is outstanding. Because of this, the bus bandwidth is shared between the master and slave devices when both are actively interacting with the host.
Serial ATA – Point to Point Connections for Dedicated Bandwidth
Serial ATA uses a point-to-point connection topology, meaning that each source is connected to one destination. Each channel has the capability to work independently so that there is no contention between drives and thus no sharing of interface bandwidth. This connection strategy also negates the need for master/slave jumper settings on devices.
It appears the newest design for SATA allows for speeds up to 3 Gb/s (that's giga-bits, not giga-bytes), but according to the specs, allows for only one drive per interface. Meanwhile, my Ultra320 SCSI controller has 5 interfaces, each capable of handling up to 16 drives, at a speed up to 320 MB/s (that's Mega Bytes), which equates to 2560 Mb/s. Not quite as fast as the SATA, but remembering that I can hook much more than one drive up, I can get parallel access (RAID x0, where x is 1, 5, or 0) to get
much faster speeds.
It would have been nice to see SATA beat out SCSI, but it can't by its very design.
