I have a serial ata pci card with two hard drives on it for storage. I am listening to Itunes and typing a paper when the whole comp freezes. I reboot and the system hangs at my SATA controller card. I reboot again, same thing. I unplug the two extra hds on the controller card and take out the controller card. boot the system and everything is fine. What might be my first attempt to find out what is wrong? Is it the controller card or one/both of the hard drives?