Take a look at your Mobo, if you see a chip with SATA-link on it then your problem is that your SATA controller is using the PCI controller for indirect Drive control ( a bit like using a PCI SATA card). 66mb/s is about as fast as you can go. If your PC has a dedicated direct SATA controller, then you might have a first generation drive. Even the latest HDDs aren't much faster than thier Ultra ATA 133 counterparts, (they are basically the same, but with a Serial to SATA converter.)