Hi,

I've tested two modern 24x10x40 CD-RW drives in my PC (an AOpen
CRW2440 and a Plextor 24/10/40A), and found that the CD-R's they burn
are not as reliable as those written with an older, much slower 6x4x24
drive.  I'm not sure if the media type matters, but I've been using
reasonable quality, brand name CD-R's rated up to 32x (max), like
Memorex and Samsung media.

I've used the same program for all these tests, NTI CD-Maker Pro (a
popular CD-burning application).  My OS is Win98SE, I'm positive all
the settings are correct (DMA is enabled, "auto-insert notification"
is turned off, etc).

Although the newer drives write very quickly (and don't make
coasters), my DVD-ROM drive has trouble reading portions of burned
CD-R's (it slows down periodically), and a scan with Nero's free "CD
Speed" program (www.cdspeed2000.com) shows "damaged sectors" on the
discs and a lowered "cd quality check" rating.

There doesn't appear to be a problem with lost data, just increased
error rates on the discs.

Again, this never happened with any of the 6x or below drives I've
used.  Do you have any explanation for this phenomenon?  Do you think
these discs with "damaged sectors" might not last as long, or have
issues with future CD-ROM drives I might buy?

Hello core-ga!

I think I know what your problem is, I've experienced it myself. For
what you state in your question, you're probably getting "buffer
underruns", which are more likely to happen the faster the cd writer
is. You can find an explanation of what a buffer underrun is at this
site

Buffer Underrun Technologies
http://www.burnworld.com/cdr/hardware/bu.htm

Basically, this is what happens: while recording a CD, data is
transferred from the source to a "buffer memory", and after that it's
sent to the recorder and erased from the buffer memory. A buffer
underrun occurs when the recorder tries to get data to write from an
empty buffer memory. In this case, your CD burner will leave a
non-recorded gap in the blank CD, which will be either read as an
error by CD players, or it will slow down the reading.

Why would the buffer memory become empty? Because the source could
have stopped sending information to it. For example, if you are
copying data from your hard drive and another application is started
(for example, a screen saver), the hard drive will slow down, so it
will not be able to "refill" the data that was sent from the buffer to
the CD recorder. Now think about it, with slower write rates (like
6x), it's very unlikely that the buffer will become empty before data
is sent again from the source; however, at high speeds (like 24x), if
your hard drive can't keep up with your recorder's speed, the buffer
will empty and an underrun will occur.

While it's true that newer CD recorders have the BURN-proof feature
built in, which supposedly eliminates buffer underruns, this
technology sometimes fail, and a gap may be recorded anyway. In any
case, please make sure that your NTI CD-Maker software is recognizing
this technology and that it's enabled, otherwise your CD recorder will
not use it. To learn more about burn-proof, you can check:

Burn-Proof
http://www.burn-proof.com/

As to your second question, I don't see why this CDs shouldn't last as
long as "normal" ones. I do think you will have trouble with some some
CD-ROM drives. I have two CD-ROM drives on my PC (Sony and Toshiba),
and sometimes the Toshiba isn't able to read some burnt CDs, while the
Sony can. In any case, before burning CD, always remember to disable
any applications that might be slowing your system; and instead of
making CD to CD copies, try first making an image of the source in the
hard disk, and then burning the image into the blank CD.


For more information on buffer underruns and burn-proof, try:

Arche Technical Web (search for burn proof)
http://www.arche.co.nz/technical/current_issues.html

I hope this was of help. If you need more information, please request
a clarification, I'll be glad to do further research on the subject.


Best wishes,

elmarto-ga

---

Clarification of Answer by elmarto-ga on 12 Jun 2002 22:47 PDT

I almost forgot... try using Verbatim CDs. I have achieved the best
results with these, and most people I know tell me this brand works
great for them too.   

---

Request for Answer Clarification by core-ga on 12 Jun 2002 22:52 PDT

Anyone else want to try this, or how can I get a refund for this
answer... it isn't correct.   

---

Clarification of Answer by elmarto-ga on 13 Jun 2002 10:22 PDT

Hello core, 
 
I'm very sorry this is not the answer you were looking for. If you
wish, you may apply for a refund at
 
<a href="https://answers.google.com/answers/main?cmd=refundrequest">https://answers.google.com/answers/main?cmd=refundrequest</a> 
 
I hope you don't give up using Google Answers, as most people is
usually satisfied with the answer given. For your future questions, I
suggest you include as much detail as possible. Had I known that you
have a 7200 rpm hard disk, or that you have tried recording at lower
speeds with the newer drives, I wouldn't have thought of buffer
underruns.
 
Anyway, I blew it. Again, I'm sorry, and I hope you try reposting this
question after getting a refund; I'm sure you'll get the answer you're
looking for.
 
 
Regards, 
 
elmarto-ga 

The answer is unsubtle and just plain incorrect.  It begins with "I
think I know what your problem is," (researcher thought wrong).

Nope, it's not buffer underruns.  For one thing, Plextor drives (in
particular) have 4MB buffers and "Burn Proof" (which is designed to
protect against buffer underruns)  When I made these tests, I wasn't
doing anything else on the computer, and also I have a 60-gig 7200RPM
hard drive.

And this one clinches it: I get the "bad sectors" even when writing at
a slower speed (like 8x) with these "newer" CD-RW drives.

If it were as simple a problem as buffer underruns, I could have found
the answer in my Plextor user's manual or the online help that comes
with NTI CD Maker Pro... which is why I'm paying for the answer here
:-).

Hi core,

I think you might have been a bit too quick to rate elmarto, before
giving him the chance to make you happy.

Best bet, to make sure you get the answer you want, is to post a
request for clarification, and wait for the Researcher to answer that
request.  It might take a day (especially at this hour!), but we
always try our best to get back to our customers ASAP!

Thanks for giving us a spin.

missy-ga

From the Answers Help & Tips Section:
( https://answers.google.com/answers/help.html )

Ask for a refund 
To request a refund, you'll need the question ID number for the answer
that is unsatisfactory. Go to "My Account" and select "Answered
Questions." Choose the question for which you would like a refund. You
can see the ID number in the right side of the window. While keeping
this window open, launch a second window in your browser (Ctrl+N in
Internet Explorer). Type or paste the ID number into the "Question ID"
space on the refund page. Please supply the reason for your request -
your refund cannot be processed without this explanation. The reason
will be posted on the site along with the question and answer since
this will provide useful information to other users.

Unfortunately, there is no "refund page," online help or not!

Sorry for rating too quick too, I'm entirely new to Google Answers (+
I know it's still in beta).  But experiences like this are enough to
make me just want to do my own research (actually I've applied to be a
researcher, but think I blew the second part by not sticking closely
enough to the guidelines).

Ah well... if anyone is good enough to help, I'm all ears, and do
appreciate it.

Cheers...

the Researcher totally got the answer wrong. he made it clear that the
disk just contained errors, not totally ruined due to a
buffer-underrun.

Hello again, core,

There is a refund page, if you don't want to wait for elmarto to
clarify (but I hope you will wait to see what he has to say!).  The
direct link is here:

Refund Request 
https://answers.google.com/answers/main?cmd=refundrequest

Make sure to put your question ID (25064) in the box as indicated.

During the Beta, we're all learning as we go.  I hope you'll come back
and learn a little bit more with us, with another question or two.  I
posted a question myself yesterday and discovered that it was almost
as fun as researching!  The hysterical commentary alone was worth the
$10 I paid for my answer.

Suicidal Chipmunk?
https://answers.google.com/answers/main?cmd=threadview&id=24343

missy-ga

Thanks Missy, but where *real money* is concerned, my sense of humor
doesn't have much staying power.  Maybe you have $10.00 to throw
around on "suicidal chipmunk" questions, but I'd rather use it for
grocery shopping.  It's not hard to find a *free* laugh (and probably
an answer, too) on one of the thousands of web-boards, newsgroups and
such that are available.

I really don't think I'll be using Google Answers again, since there's
always a chance of getting a "software support desk-like" answer
(reminds me of when I called paid Microsoft support back in 1994,
arrrrrrgh).  Nor do I think Google really has this well-organized, or
has very good criteria for selecting researchers (they should be
requesting 'real-world' resumes as well).

Anyway, have fun and enjoy,

Tim