dai

there should be a label on the m/b or it silk screened on
the original sata was called sata and ran at a speed of 150
then came sata 2 that runs ata speed of 300
with only 2 sata ports it sounds like it may be an old sata board and not support sata2
in that case you just have to put a jumper on the back of the drive limiting it to sata 150
cannot tell if you need to upgrade your psu unless you post your system spec and the psu details