I am trying to add an addition hard drive to the E521. The manual says to attached the data cable to SATA1 or SATA0. I can't find these on the motherboard. I can find SATA2 and SATA3. The motherboard diagram in the manual does not match the motherboard.
Can I attach the data cable for the second hard drive to SATA2?
Yes, you can attach to any SATA port. When you boot up, go directly into BIOS Setup and just verify that the SATa ports are all Enabled and you new drive is detected there. Save and Exit as necessary.
When you get into Windows, probably you will need to Partition and Format that new drive using Disk Manager before Windows can see it and use it. Alternatively, go to the website of the maker of your new drive and download their utility to prepare a new drive for use.