Storage Hardware DevicesStorage HardwareSlide 3Magnetic DisksHard DisksHard Disks Cont.Optical Disks2 Different Optical DisksSlide 9USB Storage DevicesSlide 11Slide 12Slide 13Brand NamesPrice RangeSummary of Storage CapacityStorage Hardware DevicesPresented byHector ArreolaValentin KifumbiKeely Ritchie-BolandStorage HardwareHardware that saves data and programsNonvolatile MemoryMemory that preserves data contents without powerVery reliableHowever, they do occasionally failStorage Hardware DevicesMagnetic DisksHard DrivesOptical DisksCDsDVDsUniversal Serial Bus (USB) Storage DevicesMagnetic DisksUse magnetism to store data on a magnetic surfaceHard DisksA type of magnetic storageRecords data onto platters coated with a thin layer of magnetic materialUsually installed inside the computer's caseHard Disks Cont.Rotational delayThe faster the disk spins, the shorter the rotational delaySeek timeDetermined by the make and model of the disk deviceOptical DisksCircular disk made of plastic and coated with a photosensitive materialTiny pits store dataDigital data (1’s and 0’s) read by reflection2 Different Optical DisksCDData layer is near the top of the discDVDData layer is in the middle of the discCan have data in two layersHave greater capacity and speed than CDs2 Different Optical DisksThree different types of CDs & DVDsRead-only Memory (ROM)Recordable (R)Rewritable (RW)CDs & DVDs can be used as storage but main use is entertainmentUSB Storage DevicesA of flash memory storageSolid-state devices (no moving parts)Read and write data electricallyMemory stored on a small printed circuit board Advantages over other storage hardware devicesMagnetic DisksLong term nonvolatile dataRotation delay: Time it takes for the data to rotate under the read/write head. Seek time: Time it takes to read/write arm to position the head over the correct circle.Faster spinning disk means shorter time delay.Channel: Common standard is the ATA-100, transfers rate is 100MB per secondOptical DisksSome are read only memoryCD: Maximum capacity of 700MBDVD: Maximum capacity of 4.7 GB with a Transfer rate is 10 times faster than CD.Today every computer should at least have a CD-ROMHard DisksCapacity: The number of bites it can hold. Its between 10 and 40 gigabytes.Data rate: The data rate is the number of bytes per second that the drive can deliver to the CPU. Rates between 5 and 40 megabytes per second are common. Seek time: The seek time is the amount of time between when the CPU requests a file and when the first byte of the file is sent to the CPU. Times between 10 and 20 milliseconds are commonBrand Names-IBM-Toshiba-San Disk -Sony-Philips-Seagate-MacromediaPrice RangeSummary of Storage CapacityMediaGood for
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