I just got a used Optiplex GX620. I can only get the "0" drive sata channel to work. I wanted to add a second drive but it is not seen in the BIOS when attached to the "1" channel but is seen when attached to the "0" channel. Also, the original drive is not seen when attached to the "1" channel. Thus I have two good HDD but only on active channel. I have also turned all the SATA channels "ON" in the BIOS. Any help will be appeciated.
I have the exact same issue. i have been pulling my hair or for a week. Foods you ever find a solution?