my hdd (a generic WD 5400 rpm 640GB hdd came with my Acer Aspire 4752) announced that it is dying on a windows 7 pop up 2 years ago. I run sentinel and it seems to confirm it. Since I have a backup on cloud and on a second tower, I reset windows which was chugging at the time and is unable to do anything as every 2 minutes or so it would either freeze before recovering moments later or outright bsod when trying to do some stuff too extreme apparently such as running crystaldiskinfo. After resetting windows 7, still got the same S.M.A.R.T warning so I remove partition and merge them into one and proceeding to upgrade for free from windows 7 to windows 10 pro. after I upgraded windows, the same darn hard drive occasionally chugs (which is apparently normal for a windows 10 on a hard drive) but it still works fine even after having the entire adobe cc suite installed and have since rendered several videos for me with that drive as the scratch disk. is the crystaldiskinfo, sentinel and S.M.A.R.T softwares all lied or windows 7 is faulty??? I can run the machine now and give you guys the ss of the diagnostics if needed but it runs fine. even faster than my grandmother's 1 year old Lenovo Yoga which happen to run a similar drive.although I noticed the maximum capacity has been decreased and once, windows 10 fails to boot and needed to be loaded back to the old saved whatever it is they do on the windows 10 diagnostic screen. also, it is obviously out of warranty since I bought it back in 2012.