Nero Buffer fluctuates

vbimport

#1

I wanted to ask a question about about my Buffer. When I’m burning a CD-R/RW at 4x everything is fine, but if i burn higher than 4x the “Used read buffer” bar and the “Recorder buffer level/state” bar fluctuates all over the place. Same thing with DVD’s and it does this whether I’m multitasking or just burning. I’m wondering why that is and is that dangerous to my discs? I have burned successfully without any buffer underuns and played it on my dvd player without any problems. I just wanted to know what that was about. Could it be because my PC is slow? I’m on a PIII 600 256Ram laptop. I’m just worried my discs will not burn properly and have some sort of glitches or skipping in the middle of the burns. I don’t want to have to burn every 4 gig file and watch it from beginning to end. I’m using 1633sx liteon with BSOS firmware on usb 2


#2

sounds like a DMA issue


#3

there is no DMA. its USB2.0


#4

The buffer underrun technology will keep the unit from running out of data to avoid an error. The cpu speed and memory size has alot to do with it but I wouldn’t worry to much about it. Your burns should be fine


#5

Do you mean the Smart-Burn feature? That feature is only activated during CD burns but not DVD. Here’s a pic of how it looks when I’m burning a DVD.

The Used Read Buffer goes as low as 1% and jumps all over the place, same with Recorder Buffer Level/State.

Like I said before though, I’m not getting any coasters. It burns succesfully and plays w/o any glitcfhes in my DVD Player. I’m just concerned that it’s not burning properly and may cause problems later down in time?

The requirements on the 1633SX box saids PIII 450mhz 128MB Ram win98/me/2000/xp.
I’m on a P3 600 with 256MB Ram and 98se, so I dunno. Should I be worried or not? I have yet to burn my stuff off my hard drive because I’m worried about this.


#6

i was under the impresion that dma had to be enabled what ever the device, sorry if i was wrong, but hey were all here to learn arn`t we.

have you tried doing a burst rate test with nero cd speed?


#7

Buffer underruns do cause quality reduction. There are small gaps between the burned sections of the disc because no burner can perfectly resume the burn. I’ve noticed that one of my fussier CD players, for example, chokes on a disc that had buffer underruns (lots of skipping) whereas a clean, non-underrun burn plays cleanly. Some of the newer buffer underrun technology (like Seamless Link) works better and the gaps are smaller but they still exist.

It’s always better to be able to burn a disc cleanly if you can. Avoid multitasking when you are burning. If you really need to multitask, burn at a slow speed, like 2.4x or 4x (8 or 16x for CD).

You say that your DVD burner is on a USB cable so DMA doesn’t matter, but where is your data coming from? If your local hard disk, is DMA enabled on your hard disk and its IDE channel? You have to not only be able to push the data to the DVD burner fast enough, you have to get it just as fast too. If you’re burning off a network device, you are going to get lower throughput than if you burn off a local hard disk.


#8

I’m not sure that I subscribe to your theory Jim on the first part of your post. Buffer underruns occur when the data stream cannot keep up with the burner. What Buffer underrun technology does is to tell the burner to slowup…not stop. At a slower burn you should get better quality burn. I think that maybe your fussy DVD player maybe due more to the Brand and type 0f DVD you are using and the bookmark setting


#9

“Buffer Underrun Prevention Technology is a new technology that automatically prevents buffer underrun errors by predicting them before they happen.
Dual drive features Buffer Underrun Prevention Technology to enable stable writing in the following situations where buffer underrun errors may otherwise occur in a conventional drive”. According to what I could find the BUPT works on both CD & DVD. All it does is when the data stream can’t keep up with the recorder, it tells the recorder to slow down until the data catches up so you will not get a crash. It will not hurt your writer. Theoretically the buffer read should be higher for a faster burn. I did a snapshot right after I started this burn and the buffer did show steady until about 3/4 of the way through the burn where it started to drop to 6 or 7% and then backup but I was multitasking at the time so this is normal. Make sure your using USB2.0 and have the USB enhanced driver installed and your DMA is enabled for your hard drive. That is about all you can do other than a faster system

P4-2.86MHZ–MSI 865Neo2-pls 800FSB M/B–1gig DDR2 memory–2 Maxtor 120gig 7200rpm
SATA Drives–ATI 9800Pro 128 Graphics–Liteon 52246S CDRW—Nec3520 DVDRW


#10

Buffer underruns occur when the buffer empties. If the buffer isn’t full but is emptying faster than the computer can fill it, then yes, slowing down the burn can help, but if the buffer empties, the burn must stop. This creates a gap in the burn.


#11

Thats the whole point of the Buffer underrun technology on the new DVD/CD-rom drives. It doesn’t allow that to happen any more. The buffer never empties. The drive is slowed down to match the input stream.


#12

I don’t know what you mean buffer underuns cause quality reduction? If theres a buffer underrun, doesn’t the burning process fail? My DMA for the local hard disk is enabled but still fluctuates. It doesn’t matter if I multitask or not, it fluctuates no matter what. I can’t burn lower than 4x.

So my question is if theres nothing I can do to make the buffers steady, is it still something to be concerned about or is it fine as long as the program does a complete burn? Will I be burning DVD’s that will have problems down the line, etc?


#13

try installing this ForceAspi:

http://forum.cdfreaks.com/showthread.php?t=101614


#14

No it is not something to be concerned with.