Hi, my SCSI "15k Seagate Cheetah" is not showing me performance improvements over my SATA Hard Drive.

Specs:

*WinXP Pro (PC).
*Adaptec ASC-29160N PCI Ultra 160 SCSI Controller Card
- Adaptec ASC-29160N PCI Ultra 160 SCSI Controller Card - eBay (item 110276634335 end time Aug-10-08 15:41:18 PDT)
************************************************** **

any ideas why my setup shows no improvement over my SATA?

Thanks.