Data transfer rate: The higher the data transfer rate, the better, but the more expensive.

Access time: The lower the access time the better. Access times usually range from 85-500 milliseconds.

Disk cache: Sometimes called a buffer. Most CD-ROM drives come with a 128-256K cache.

SCSI or IDE: If you choose SCSI make sure your CD-ROM drive includes a SCSI adapter. If your CD-ROM comes with a sound card, a SCSI port is included on the card. If your motherboard has IDE this would be a cheaper alternative to SCSI. Most CD-ROM drives include both SCSI and IDE support. SCSI will generally give you better performance, but is more expensive.

Caddy: Some CD-ROM drives include a caddy for loading CDs. This is a special container for your CD-ROM disk. You put your CD-ROM disk in the caddy, and put the caddy in the drive. If you plan on mounting your drive vertically instead of horizontally, you must use a CD-ROM caddy drive.

Bays: All of your drive bays used up? You can buy an external CD-ROM drive. These drives are portable and connect to a port in the back of your PC. These drives are easier to install, but are more expensive.

Other Features: Are you interested in playing audio CDs? How about using Kodak Photo CDs. Most drives come standard with these features, but some do not. If you are running Windows 95 or later, you may look for a plug and play CD-ROM drive.