should I be concerned about the Device Buffer running low?

[broadway]

As I wrote in another post, I bought the NEC 3520A.

I usually use DVD Decrypter to burn an ISO file.

I've notice that with the NEC, I will sometimes see it momentarily pause for the briefest second and see the Device Buffer drop to 0. I am using 4X media and telling DVD Decrypter to burn at 4x. Should I be worried about the burned DVD? I never saw this problem with the LG-4082B that I had.

[jtoolman2000]

Usin gthe same drive and progs I see that but only when burning at 12x. Decrypter iso burn will start up at a max 4.3x and about 1/3 of the way it will shift up to about 8.3x followed by a final 1/3 at about 12.1X It is when it is "Shifting" that I notice a temporary drop in the buffer. I need to be carefull that I am not running anything else nor playing around in the internet. Specially as it reaches the higher speeds or it will throtle back on its own. I don' 't know why it is doing that at 4x as it should be burning at a pretty constant speed. It's onlw with 8x and higher that you see the speed shift.

[broadway]

I should say that I have a 1GHz P3, so maybe that's a reason...

[Supreme2k]

Have you tested at 2X to see if it still pauses?

Do the burns complete correctly? If so, nothing to worry about, though you may want to turn all other heavy tasks off.

[broadway]

No, I haven't tried it at 2x. I thought that if it was able to burn at 4x with the LG-4082B which admittedly may be a "slower" burner than the NEC that I should be able to burn at 4x with the NEC.

It finishes up okay. I did a "verify", and it reported no problems.

Are there any programs I can use to verify that the burn was okay?

[henry_nettles]

Unfortunately, Nec burners do not support disc quality testing, or "scanning" as it is more commonly called. The only burners which do are those made by Plextor, Liteon, and Benq. The best you can do with your Nec is to run the Transfer Rate test in CDSpeed, which you can download here:

http://www.cdspeed2000.com/go.php3?link=cdspeed.html

[samijubal]

I burned many discs in Nero with no burner buffer at all, only the Nero ultrabuffer, which would drain once or twice per burn, then the disc would wind up and down a few times then start burning again. I never had any problems with the discs. I've since gone to Decrypter just to be on the safe side. I can tell you from experience that the buffer underrun works very well on the NEC 3500, so you should be OK.

[Tidy]

Check the write strategy for your burner that may explain why you see the momentary buffer drop thent hings speeding up again.

[broadway]

Check the write strategy for your burner that may explain why you see the momentary buffer drop thent hings speeding up again.

what do you mean by write strategy?

[Tidy]

Write strategy is the method that is programmed in your firmware that it uses to burn discs if it uses ZCLV then you will see these slow downs you will also most likely see burn rings as well.

[bbanderic]

This is normal with the NEC 3520, mine does the same thing about 4 times per burn, I use DVD Decrypter as well. The device buffer will go down to about 3% for a brief second but if you notice the used read buffer will remain full. This was discussed on another forum (check CD Freaks NEC Forum) and supposedly the burner is recalibrating itself when this happens.

[Tidy]

It is most likely the speed shift from the write strategy

[Bondiablo]

I just noticed this on my NEC 3500 and it does appear to happen at speed changes. The reason I noticed it is, for the 1st time, I burned several DVDs at near the capacity of the media and, with any over about 4.2GB, during play back most of them freeze near the end of the last track. After watching several burn with DVD Decrypter I noticed that the device buffer never drops below 92% with my +RW media and those discs play peferctly all the way through to the end. With the 2 brands of 8x +R media I have, even at 4x, the device buffer bottoms out several times during the burn and (though the burns always appear to finish successfully) if it happens too many times those discs fail the write verify and freeze near the end during play back.

[Skith]

This has to do with the the write strategy (Z-CLV) that the drive uses. It is perfectly normal for the buffer to empty when the drive shifts (increases) speed.

[Bondiablo]

Even writing the disc at 2.4x the same thing happens and it always seems to happen about every 10 - 12% of the process. Also, if the information here in the dvd writers section is correct, these drives use CAV for R discs and CLV or ZCLV for RW and DL discs. As I said the buffer never emptied with the RW discs.

If it is normal it seems it would mean you can never write to near the capacity of the R media with these drives.

[samijubal]

I write to capacity with the 3500 all the time. I have never had any playback problems with either DVD player I use, and no one I've sent discs to has ever had a problem either. Prodisc and TY -R media.

[Bondiablo]

Does the device buffer empty for you as described above also? I'm using Prodisc PRODISCR03 and none of those work when written to near capacity, I'm actually having slightly better luck with the last few, supposedly crappy, Optodisc OPTODISCOR8 I had left. Maybe I just have a bad writter, though I can burn the RWs to near capacity every time and they work fine, or what firmware are you using?

[samijubal]

The buffer drains for a second during burns, and at every speed change. I burned many discs in Nero without any burner buffer at all, the reason I went to Decrypter, and never had a problem with a single disc. The ultrabuffer would drain a couple of times per burn, then the disc would wind up and down a few times and start to burn again. I still never had any problems with the discs. I don't use +R discs. I will bet it's media. Firmware is 2.18, I can't tell any difference from 2.16.

[WesleyHester]

This is just a test method and not a cure for cancer:

(XP Instructions)
Just before burning with everything ready to go, open the Task Manager by pressing [CTRL][ALT][DLT]. Then click on the Processes tab which will display a list of Processes in memory. Now click on the CPU Header button until System Idle Process is at or near the top of the list or everything above 00 percent is at the top of the list. (Click the CPU Header is meant to re-order the processes based on CPU usage).
Now start your burn with Task Manager running. Observe what processes are increasing in CPU usage as you burn or processes that 'jump up and down' the list frequently. If you don't spot any thing unusual then do nothing. If however you see one or more processes that 'act up' during your burn then try disabling/unloaded them and then try another burn. This technique helped me with a high speed (16X) issue I was having that before which I didn't suspect the program that was causing my issue.

[Tidy]

At this point who knows with the slow processor that could totally be it.