Connect the HDD back as it was ORIGINALLY
Boot the computer
enter the BIOS setup - NOT the one time boot order
In the BIOS is the HDD recognised - not as the boot priority boot from Hard drive
BUT in the BIOS screen where the HDD is seen with the other hard drives and the optical drive.
If the system is installed configuring IDE mode for the SATA drive and then the mode is changed to SATA the computer will not boot, as the drive will not be seen
Is that the problem.
Unless we can get that HDD seen by the BIOS which is completely irrespective of the state of the Windows O/S, the Boot configuration data - which loads Windows etc, then it is either the motherboard, BIOS or the SATA port to HDD cable, or the SATA power to the HDD
There may be other more unusual causes but those are the main.
Edited by Macboatmaster, 30 September 2012 - 05:35 PM.