回答“What is the cause of multiple hard drive failures?”Ok I have an HP Pavilion DV9700 series laptop. I bought it used from Ebay in like new condition. The owner had it stored away for some years after he bought a new laptop. Anyway, I received the laptop, booted up fine until one day it just stopped. Strange, I did a systems check everything turned out fine. Except I noticed in the bios that there was no IDE hard drive listing? Now it was really crazy. Anyway, installed a different HD samething. Hmm. Then I removed the 'HARD DRIVE COVER' and left it open so I wouldn't have to open and close to remove the HD. Believe it the laptop booted right up. So I closed the HD cover back and tried to boot and got nothing no operating system installed REALLY? OK people looks like the HD cover is the kulprit. Seems to be causing a contact issue with the HD and motherboard not being able to see the HD. Try it! Mine is uncovered and working just fine. NOTE place some tape or something to hold up your HD. Hope this helps.