Hmm... at this point, I doubt you will lose your data. It's
impossible to reformat, because Windows will give out an
error.
Let's try this.
Go into BIOS again.
Check the hard disk mode, whether it is set as Master, Cable Select
or Slave.
If it's Master, set to Cable Select. If it's Cable Select, set to
Master. If none works, change it to Slave.
Do the same for the CD/DVD drive.