P-CAV vs. CAV writing

I have recently noticed that my 1620 is writing in P-CAV and not CAV. Here is a cdspeed scan showing it as P-CAV:

Is P-CAV better or worse than CAV?

Is this dependent on the disc and speed of the burn?

Is it possible to switch between them?


What you are seeing, is that, your hardware rig can’t reach 16X burn speed. There are many reasons for this…

  1. What’s your burst rate via Nero ?
  2. HD defragged ?
  3. HD burst rate too slow ?
  4. Other programs running ?

Dont forget not enough processing power.

  1. Burst rate is 23 MB/sec

  1. Defrag 1-2 times per week (sometimes more) on all my HD

  2. Primary HD is 120 GB Barracuda SATA. Here is my IDE configuration:

  1. Nothing else is running in the background.

Here is another shot of infotool showing “processing power” on my system:

Not sure what could be the problem.
Thanks for any suggestions.

Everything looks great…
Only other thing I would try is to take the AOpen off the system and try again…
Good luck…

Could be the discs you are using as well, if the quality isnt great the drive will slowdown, what make and brand of disc are you using and what are the rated speeds?

Agree. :iagree:

Just out of the blue, have you updated to latest BIOS version.
Checking bios revisions, there have been some “Ultra DMA Mode max limit” issues on this boards, (fixed in rev. P48S1004).
Edit. From image posted above it looks like you are on bios revision 1006. Is this correct.

You can also run a transfer and burst test in Nero, see my sig. :wink:

Bios ver 1006 is the latest by ASUS

I tried using Nero for the Burst/Transfer testing, but I couldn’t get “Nero Burning Rom” up all I could do is get Nero Express and I couldn’t find out how to get back to regular Nero. I used the HD Tune that you suggest on your site.

For the test I posted above, it was a Maxell 16x disc. I only had 2 discs so I can’t do any further testing on them. I think they were Philips and rebadged as Maxell.

I ran a Tyg01 and it topped out at 12x. I am using B7T9 and MCSE to substitute the Tyg01 media code with Tyg02 media code. I am not sure why it is topping out at 12x. In this scan WOPC is turned on.

If you can tell me how to run the Burst/Transfer test with Nero Express or how to get back to Nero, I will run them later.

Thanks for all your help!

I’ve seen this sort of a writing curve occasionally, when burning images with CD-DVD Speed. BenQ and LG drives, both. I am in the same boat: 23-26 MB/s burst rate on DVD drives, 50+ MB/s when copying the same images to another hard drive. Incidentally, that’s not really P-CAV, it’s just the drive struggling with the internal 2 MB hardware buffer not being refilled fast enough; running out of data to burn, pausing, resuming the burn, that sort of ugliness leading to the complex shapes you are seeing at the end of the 16x burn. Your 12x burn is what P-CAV looks like.

Never happens when I burn with DVD Decrypter and a 256 MB buffer. Make your own conclusions!

lantern, thanks for the info posted. Looks like we can forget about the “DMA mode limit bug”.

From your pics I see you have two HDD´s, one old 40GB Maxtor and a Seagate 160GB SATA.
Where is/are your OS and programs installed? Reason I ask this is because your Maxtor is old and slow (5.4k rpm) and can be a bottleneck in your setup.
Run HD-Tune on that drive also.

Dont know what version of Nero you have but you can d/l a (full) demo copy here.
Please wait with install because you might also need Nero clean tools…

@agent009, interesting (new) theory you put forward about “unsufficient” internal hardware buffer.
I’ve hard to believe either drives hardware- or Nero CD/DVD Speed buffer has anything to do with it here… :wink:

Take note esp of this point when it comes to CD-DVD Speed burns cos I think it does not do any data buffering in RAM at all so any file fragmentation can cause such problems.

My own personal experience.

My OS and programs are on the Seagate. I only use the Maxtor for storage.

As for Nero, I am using an OEM version and have it updated to the latest version. If I install from your link, will that use the serial number I already have in use?

I ran a test this morning with a different disc, I used a Teon 8x (CMC Mag E01). I have the write strategy changed for this to allow for 16x writing. Here are the results.

This reached the 16x and used CAV. Write time was 6:19. Not the greatest, but at least it got up to 16x! I hadn’t realized that the write mode used would be disc dependent, especially when I was actually using “real” DVD+R 16x rated media before. I guess that the media was just crap. I thought that the Philips media was supposted to be decent.

My only other question is, why would the TYG01 DVD-R top out at 12x even though I have the write strategy changed to allow for 16x writes? I suppose that I should be lucky it isn’t stuck at 4x!

Thanks for all the input!!!

I’m glad you made it. :slight_smile:

As for Nero, I am using an OEM version and have it updated to the latest version. If I install from your link, will that use the serial number I already have in use?
Don’t know because there are many OEM licensed versions of Nero.
You will know it after you try it out, but you can always go back to your OEM version of Nero.

My only other question is, why would the TYG01 DVD-R top out at 12x even though I have the write strategy changed to allow for 16x writes? I suppose that I should be lucky it isn’t stuck at 4x!
Probably WOPC limiting your burn. I’ve never been able to burn TYG01@TYG02 higher then at 12x…


I have the same problem with my PC and my BenQ DW1620 (FW B7T9 RPC1 speedpatched)…

media I use momentarily is Verbatim MCC 03 DVD+R 8x certified @ 12 X speed…
I will include info ofNero InfoTool (txt-file), mayB that might be helpful as well as a link to pic of recent create disk session in Nero CD-DVD Speed.
Here: http://club.cdfreaks.com/showpost.php?p=986155&postcount=1191

Furthermore, I did do the HD burst rate test described by pinto2…
Here’s what I get (using that same 8X certified media, have no other @ the moment :()

  1. [li]HD Speed test: (1 HDD of 80 GB with 4 partitions)
    [/li]C:\ Drive 39.488 kB/sec
    D:\ Drive 39.040 kB/sec
    E:\ Drive 28.582 kB/sec
    F:\ Drive 22.976 kB/sec
    [li]Speed measurement (last step of guide)
    [/li]Speed measure: 23,6x
    Time consumed: 02:31

I have Raxco PerfectDisk as a Defrag tool, and set it to defrag my disk every 2 weeks.

What is running in the background (in system tray is just a scheduler and the guard portion of my antivirus program, called AntiVir :smiley:

Can any1 help me out, besides telling me that I mayB need a newer PC hehe
Don’t have the money right now (student)

Nero InfoTool.txt (27.5 KB)

mindwarper, out of the feedback I got from my transfer test, you need at least 2x the speed that you want to burn at, to ever be able burn without issues…
Out of this, you need 2 x 12x x 1.350 = 32,3x, compared to your test (23,6x), that is just enough for 8x burns…

(I get approx. speed of 37x with MCC003 Verbatim DLP.)

Most probably the bottleneck in your setup is the mobo. Right now your mobo runs at 66 MHz fsb speed. Have you had a look into BIOS if you can speed up this (maybe to 100 or even 133 MHz)?
[Yeah, I know there are other issues that may occur…but no need to worry.]
This might be of interest if you can’t change fsb speed and/or other settings with current (original) bios.

Download CPU-Z to check your settings and changes.

That is funny cos my FSB is 133 MHz as reported by CPU-Z (see attached Cpu-z.htm in zip file)

MayB it is time to get me a new PC altogether soon anyway…

cpuz.zip (1.32 KB)