I have a Dell Dimension XPS 720. My PC has two sata hard drives and one IDE hard drive. When I boot the PC tells me that it doesn't detect any hard drive in sata 3. Then it asks me to press F1 to continue. But, when I get into my OS which is Vista Ultimate, I check 'My Computers' and my second hard drive appears. And sata hard drive works fine. I've gone into BIOS. Each SATA port also lists the model number of the sata hard drive, but the sata drive I'm having problems with isn't listed and yes the hard drive sata port is set to 'ON'. I should also note that I never used to have problems with this hard drive in the past. It used to show up on the BIOS drive list. I need help fixing this problem.