Diagnosis: RAM power
• Data can be stored on many different storage devices such as read-only memory (ROM), random-access memory (RAM), hard disk drives, solid state drives, compact discs, and many others.
• Hard-disk drives store data on platters using an arm with an apparatus that reads and writes data by changing the magnetic domains. These data remain on the disk until they are overwritten or reformatted. Disk drives can be removed and installed on another computer without losing data.
• Solid-state drives, unlike hard disk drives, use integrated circuits and store data on a foundation of transistors that form grids. The data are nonvolatile and rewritable. Solid-state drives can be removed and moved to another computer without losing data.
• Compact discs (CDs) and digital video discs (DVDs) use similar technology to store data on polycarbonate plastic discs. A laser burns “pits” and “bumps” into the plastic, which can then be later read by an optical system. The CD or DVD can be removed, stored, and then read again by a CD/DVD player.
• ROM is a nonvolatile storage device that is preprogrammed with data and programs by the manufacturer of a specific device. In computers, firmware is stored on ROM. ROM is generally not modified within the functioning life of the device. Non-rewritable CDs can also be considered a form of a read-only storage device.
• RAM is a volatile memory device that is often referred to as “computer memory.” It allows storage of data that can be quickly and easily accessed. The design on integrated circuits allows the data to be accessed in a random fashion rather than reading and writing in a predetermined order, such as with hard disks and CDs. Data are stored on capacitors. These capacitors will discharge when power is no longer supplied and the data will be lost.
