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CD-ROM Applications

Then there’s the question of which applications actually benefit from a faster CD-ROM drive. Most multimedia titles are optimised for double or, at best, quad-speed drives. If video is recorded to play back in real time at a 300 KBps sustained transfer rate, anything faster than double-speed is unnecessary. In some cases, a faster drive may be able to read off the information quickly into a buffer cache, from where it is subsequently played, freeing up the drive for further work. This is rare, however.

Pulling off large images from a PhotoCD would be a perfect application for a faster CD-ROM drive, but decompressing these images as they’re read off the disc results in a performance ceiling of quad-speed. In fact, just about the only application which truly needs a fast data transfer rate is copying sequential data onto a hard disc; in other words, installing software.

Fast CD-ROM drives are only fast for sustained data transfer, not random access. An ideal application for high sustained data transfer is high-quality digital video, recorded at a suitably high rate.MPEG-2 video, as implemented on Digital Versatile Discs (DVDs), requires a sustained data transfer of around 580 KBps, compared to MPEG-1’s 170 KBps found on existing White Book VideoCDs. However, a standard 650MB CD-ROM disc would last less than 20 minutes at those high rates, so high-quality video will only be practical on DVD discs, which have a much higher capacity.

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