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What To Look For
Recommendations

Already know what a CD/DVD-ROM Drive is and what to look for?  Then skip to the Recommendations. 

What To Look For:

• SCSI CD-ROM drives and burners used to be a good choice, but now there are so few available that IDE is the best option. 
• Transfer rates are quite important, but it is not a good idea to just go by the 32X, , 48x, 52x, etc. ratings as they are usually not very accurate.  These numbers are supposed to indicate how many times faster the drive is than if it were being played at its default speed (the speed at which you listen to an audio CD). Usually, these numbers only represent the maximum speed these drives can reach. Thus, it is better to compare average sustained transfer rates (not always reported).
• For CD-ROM burners, it is mainly important to look at the X rating.  Look for a burner that writes at 48X or 52X as they are not much more expensive than the older, slower writers (but are a little faster). The law of diminishing returns starts to come into play with these faster drives though, so don't be concerned about the difference between 48x and 52x (it's only going to be a few seconds). The RW (rewrite) speed is how fast it can write to CD-RW discs. This is usually lower than the write speed, and is only important if you plan to use rewritables (which you can write to, erase, then write to again).  Look for 24x rewritable speed.
• The access time is also very important.  This is usually measured in milliseconds and an access time of 85 ms is sufficient for a CD-ROM drive. These numbers are usually a lot higher for burners. 
• Like hard drives, the amount of cache is also important. This can range from 64k to 512k, all the way up to 8 MB for CD Burners. 256k is a good number to look for, but 512k is preferred.  For CD-ROM burners, look for at least 2 MB of cache as this cache is VERY important in avoiding bad burns (wasted CDs). 2 MB cache buffers should prevent this from happening often.  Of course, the higher the better!
• rpms are also important, but usually are not given. 
• In general, there is not much price difference between the slower and higher speed CD-ROM drives.  Anything around 50x is sufficient, and I still think the older 32x drives are sufficient since CD-ROM drives aren't used for large transfers very often. One thing to consider is that the higher speed drives spin faster, which causes them to vibrate and make more noise, and also makes them more prone to failure. It may be a good idea to get a slower speed drive just so that it will last longer and be quieter! 
• Brand can also be important. There are two brands of CD-ROM drive (and burner) that clearly stands out from the rest, and they are Plextor (a pricey brand) and Lite-On (a very inexpensive but surprisingly high quality brand).  These drives are much faster and much more reliable than other brands.  The X ratings of their drives are also more accurate (a Plextor UltraMAX is rated at 40X, but is actually faster than the so-called "72X" drives).  Plextor's drives are superior quality throughout, but they're pricey and harder to find these days.

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