there are two possible sources of trouble:
- faulty Sata cables and
- Nvidia Sata drivers
At first, I'd try if a new Sata cable does help.
Additionally, you may try either MS standard IDE drivers or latest drivers from Nvidia. To use MS default drivers, you need to run the Nvidia installer located in Add/Remove Software (in Control Panel) and select the IDE/Sata drivers to uninstall. Note, this is not an option if you are running a Raid configuration for your HDDs.