as i told, S-ATA has more transfer rate than ATA, also its HOT-SWAPPABLE, means u can unplug the hard drive while in running condition, (but this isnt any advatage in my opinion), as no body at least will be changing hard drives opening their system casing while pc is running.
yes u can use 1 H/D making it S-ATA and increase your transfer rate.
remember, its the S-ATA technology that helps the data trasnfer rate to increase, not the hard drive itself.
Intel Core2Quad 2.66Ghz 12MB L2-Cache
4096MB DDR Kingston Hyper-X
XFX 9600GT AlphaDog
Seagate 2 X 320GB SATA2
LG L246WH Flatron 24"