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50x CD-ROM

See CD-ROM drives.



CD-ROM drives

Most optical drives today are combo CD/DVD drives that support DVDs and all the CD formats: CD audio, CD-ROM, CD-R and CD-RW. The speeds of the drives are rated by their CD-ROM and DVD transfer rates. The original CD-ROM drive (1x) transferred data at 150KB per second. By doubling the spindle RPMs, the data transfer rate increased to 300KB/sec (2x) and so on. See CD-ROM and DVD drives.


   CD-ROM      CD-ROM
   X Rating    Data Transfer Rate

      1x       150 Kilobytes/sec
      2x       300 Kilobytes/sec
      4x       600 Kilobytes/sec

      8x       1.2 Megabytes/sec
      10x      1.5 Megabytes/sec
      12x      1.8 Megabytes/sec
      20x      3.0 Megabytes/sec
      36x      5.4 Megabytes/sec
      40x      6.0 Megabytes/sec
      48x      7.2 Megabytes/sec
      50x      7.5 Megabytes/sec
      52x      7.8 Megabytes/sec


What Does 40x/12x/48x Mean?
CD drive ratings are designated with three speed numbers such as 40x/12x/48x or 40/12/48, as follows:


  First X     /  Second X     /  Third X
  CD-R write  /  CD-RW write  /  CD-ROM read





A Lot of X's
This is the label from a Memorex combo CD/DVD drive. Each "X" number means X times 150KB for CDs and X times 1.39MB for DVDs.






Personal Use Only

Before/After Your Search Term
BeforeAfter
5 nines5100
5-pin to 11-pin adapter5110
5.1 channel512QAM
5.25 inch5150
50 GbE5250
50 Gigabit Ethernet5250 emulator
50-pin Telco connector52x CD-ROM
500 error56 Kbps modem
50GbE56,000 bps modem
50GE568A

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