some misleading and incomplete info in a few of these replies. here are some important points that need clarifying. (1) SSD stands for Solid State Drive. there are no mechanical movements in these hard drives. Even if they fail, there will never be any clicking sounds, vibrations. Think of it like how a usb flash drive works. they are fast! they tend to be included with higher end systems or as aftermarket upgrades. (2) HDD stands for Hard Disk Drive. these are traditional hard drives with mechanical moving parts. Almost like a high-tech record player; there's a spinning platter that stores the data (the vinyl), and a read/write arm with a magnetic head that access the platter (not unlike the tonearm and cartridge-needle on a record player). More often than not, these are standard with many factory systems. and these make a noticeable sound when they are running (smooth high pitched whirling). if you hear clicking, then your HDD is more than likely toast. (3) my Acer has the “no bootable device” error when...