I have HP dv6600 laptop. Its windows crashed recently. After that I tried to restore a backup image created by self-image. But unfortunately backup file was corrupted and C: partition was rendered unusable. I tried to install OS anew after formatting C: drive. Again it did not succeed as the installation media had corrupted files :'( After this I tried to install OS with fresh media but the hard disk was not detected. I tried to put it into a external hard disk case but it gave beeps (not the disk motor kind of sound, but kind of when ram is not properly inserted into its slot).
I tried to put it into another desktop system (Its a SATA disk) but it hangs the system (it is running Windows 7).
On both the desktop and laptop it is detected and correctly recognized by BIOS. What are my options to get it working or at least get any data back from it?
It seems you have tried a lot, what you can still can try is running an ubuntu live disk and make a binary copy of your hard drive.
You will need 2 hard disks and a USB drive or CD. Mount both hard disks and then make a binary copy onto the other hard disk using the
Since your hard drive is emitting all signals of hardware failure, this might not work. I suggest you take backups next time.
If you have done this much to it, any data left on it will be pretty much unrecoverable. You can try a data recovery specialist , there are lots listed on Google but you will be talking LOTS of money to recover anything. You can try something like Recuva http://www.piriform.com/recuva , this will attempt to recover lost files, but after this much has been done to the drive I highly doubt it will bring anything back.
Backup Backup and Backup again, if you don't want to buy a backup device put all your most valuable data on something like Sugarsync / Dropbox / Skydrive otherwise be prepared to loose it.