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Factors In CD Duplication

The process of writing data to a recordable CD canbe a complex process, as it demands a lot from bothhardware and software programs. Much of this complexity is hidden from the user by the program,although you should be aware of these factors.

DataThe total amount of data you are writing is muchless important than whether or not it contains largeor several small files. If there are a lot of small files, the system may have problems withlocating and opening the files quickly enough tosend them smoothly to the CD recording drive.

The computerAny interruption that may occur is fatal to CDduplication, so you should ensure that your CONFIG.SYS and AUTOEXEC.BAT don't load any TSRutilities which may interrupt operations. Screensavers, alarms and reminders, or incoming faxes may also kill disc writing. You should also turnoff network sharing so no one will access the filesthat you are trying to write, as this could alsokill your disc recording.

Hard Disk SpeedTo write an image to the CD, the hard disk fromwhich you are writing must have a transfer rate that is fast enough to keep the memory buffer fullin the CD recorder. This normally means an averagehard disk access time of 19 MS or better.

DefragIf your hard drive has to search everywhere overa fragmented hard drive for the data to be written,it can cause the operation to slow down or evencause a fatal error. Therefore, always be sure tofragment your hard disk drive.

Recording speedMost new CD recorders and even some older ones,are capable of writing at two (sometimes even four)times the standard playback. It should be possiblefor you to select the speed; as even though fastrecording is a time saver, it can also cause somebad situations.

When you copy an ISO (image file) from the harddisk to a CD, the speed is rarely a problem as theimage is already one large file in which the files and structures are already in order and divided into CD-ROM sectors.

When you write from a virtual image, things canget a bit trickier. In order to copy to CD, the program must consult with the database to findwhere each file should go in the image and whereit is actually stored on the hard disk drive.

Then, it must open the file, divide it into CD-ROMsectors, at the same time sending the data in a smooth continuous stream to the recorder. Locatingand opening the file is a bit more time consuming,as writing is more difficult if you have a lot of small files.

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