Mansfield University Home PageMost new PC's being shipped today are equipped with CD-writers. All University desktop PC's purchased since the spring of 2000 have been equipped with CD writers. CT encourages folks to migrate from Zip and LS-120 media to CD's because of the increased compatibility, speed, and dramatically reduced cost of CD-Rom media. As this migration takes place, CT has received calls about different types of problems users encounter with these new tools. In this article, we'll provide some basic information as well as address some common misconceptions and potential pitfalls.
Tamela Bastion holds classes on the use of CD-R and CD-RW media. Check her training schedule or give her a call at x-4857 if you'd like to learn more about using the writing capabilities of your CD drive.
Generally speaking, the current crop of CD-Writers are capable of writing two different types of media. CD-R media is a write-once, read multiple times media that is inexpensive and very reliable. CD-RW media is designed to be read and written multiple times, like a diskette or Zip disk, and is somewhat more expensive and less reliable than a CD-R. Because CD-Roms were originally designed to be a write-once technology, the advent of CD-RW drives required some "fudging" of the original specifications in order to make the media work with PC's. Software was written that stands between the PC and the CD-RW drive to make it work interactively, and it is at that level that the problems we have seen most often occur.
Here are some basic rules of the road to insure success with your CD-writer:
Match your media with your CD-writer: Every CD writer has an ability to write up to a certain speed, expressed in multiples of the speed of the original compact disk specification. If you are using a 10X CD-writer, the media you purchase must be rated 10X or higher. If you purchase bargain media then discover you can't read the CD's you've written, overrunning the speed rating is often the cause. The control programs for CD-writers are capable of writing to slower media, but the media cannot be written faster than it's design speed. In the case of cheap no-name media, backing off from the maximum rated write speed is always a good idea, even though the writes will take longer.
Yes, you should be able to write up to the rated speed of the writer, IF the writer was supplied with your PC as original equipment, IF this is the only task your PC is running during the write AND you know your media is of good quality. When in doubt, or if writing something that's very important, CT recommends reducing the speed of the write to something considerably lower than the rating of either the CD-Writer or the media. Some experimentation is in order here, but if the success of the copy is critical, we have recommended speeds as slow as 2X for critical files.
Don't overdo it! Writing CD's takes a lot of processing power. If you're trying to surf the web, download a file and format a diskette while you're writing a CD, chances are very good the resulting CD will be unreadable. When writing a CD, it's best to close all non-essential programs. In fact, now may be a good time to review what may be running in the background on your PC, as many products are installed without our knowledge, and these can have serious effects on performance. The latest CD's have improved software and data buffers intended to minimize the chances of "buffer underrun". Some of the names for this technology are "Burn-Proof", "ExacLink", "SafeBurn" and "PowerBurn". Our advice: better safe than sorry. Close down your web browser, Instant Messangers and Email prior to starting a CD copy. And unless you have had enough experience to be certain your PC can do what you're asking of it, keep a "quiet system" while burning a CD, particularly one you can't afford to waste!
Create multiple copies! The same rules apply to CD's as any other media: Stuff happens, and Murphy's Law applies. Make certain you have multiple copies of any files you wish to preserve. Check/read your files before you archive them to insure the copy was successful. And remember: A broken, scratched or otherwise damaged CD becomes a coaster - It is never recoverable.
Not all CD readers are created equally! If you have an old machine with a slow CD drive, it will NOT read CD-R or CD-RW media. The hardware was not designed with this technology in mind.
Handle with care! Handle your CD's by the edges and keep your CD's in the shipping package when not in use. Smudges, fingerprints and dust particles can be removed by carefully wiping with a soft, dry cloth. Slightly dampening your cloth with pure water may be necessary to remove fingerprints that have been on the surface for a while. Always wipe back-and-forth, never wipe the CD in a circular motion. If you notice one of your CD's is looking a bit worn, with scratches and smudges that will not clean off by gentle rubbing, make a fresh copy while you can still read it!
Avoid Sunburning your CD's! It only takes about 100 hours of exposure to full sun to make a CD-R or -RW unreadable. Store your CD's out of direct sunlight.
Do not share CD-RW media! Our observation of CD-RW reliability is that it decreases dramatically when shared among machines. It is never as reliable as a CD-R, but is fine for daily backups and archiving. Never place the only copy of a critical file on a CD-RW disk - always make sure a second copy exists, either on your hard drive, a CD-R, or a diskette. Placing the only copy of a critical file on a CD-RW, then passing it around so different people can work on it is just as bad an idea as it was in the days of the floppy disk, and because the CD's capacity is so much higher, the potential for disaster is that much greater: This is why networks were invented! At work, use the university's network to share files, and use your CD's to keep backups and archive copies. If you want to share a file, write it to CD-R, as a permanent file; at this stage, CD's only cost a quarter, so giving them away is actually cheaper than giving away diskettes!
Don't use your CD-RW as a diskette! Don't use your CD-RW for ad-hoc copies, such as sending automatic backups of your Word documents to it. The performance of your PC will be much improved if you're working from your hard disk for your daily chores. The need to buffer data along with the write speeds of a CD stress even a fast computer, and with other complex tasks running simultaneously, the chances of damaging a file is great. Use the copy utilities that are part of your Windows or Mac operating system, as these are likely a much more reliable way to move data to CD media.