ran fine yesterday. today logged on and got blue screen with cryptic looking numbers and letters. shut down and restarted and message dell dimension 4600 bios a03 sata primary drive 0 not found sata primary secondary drive 0 not found primary drive 0 not found and primary drive 1 not found. have two sata drives. message also states and strike f1 to retry boot strike f2 to go to setup; striking either gets no results. restarted and hit f2 go to drive config able to read floppy-able to read cd and dvd drives but the sata and primarys reads unknown device. reseated hared drive cables and power cale and restarted and still no hd found. please help. am using dad's din 4700/