My computer had a 40GB Hard drive and Windows XP that was almost full so tried to install a 80GB as a slave drive. The 80GB was recycled from a different computer. It was previously the master and it had Windows Vista. I replaced the single IDE cable with a dual IDE cable, from the same computer the 80GB was recycled from and now the computer won't boot up. I tried putting the old cable back in and disconnecting the 80GB and the old 40GB won't boot now either. HELP!