Hi, I took in a older Compaq laptop with BSOD issues, the drive was not detected from dart or any of my other boot discs I ran the built in hard drive diagnostic and took over an hour and said the drive failed, as I suspected. Then I thought I'd pull the drive and put it into a bench pc and run compete WD diagnostic. Well it passed with flying colors.... Windows prompts to format the drive before it can be used. So why did the hp bios diagnostic say it's bad?