Increase write speed...?


I know my shitty system doesn`t match the burner but nevertheless I feel I should be able to write faster than 16x…

-Seagate 27gb 5400rpm set to master on udma66 (ide 1) (22958kb/s in nero)
-abit be6
-256mb sdram pc100
-plex4824a, set to master on udma33 (ide 3) dma on

(my mboard has two udma66 + 2 udma33 connectors)

Burning from image on 16x works fine…the buffer lays on 96-98% but increasing the speed to 20x the buffer decreases slowly until it reraches zero and the “burn-proof” steps in.

My hd is defragged and I am not running anything in the background.

Tried tinkering with most settings in nero, but made no difference.

Is there anyting I`m doing wrong or do I just need a faster system…

It looks like your CD-Writer is running in PIO mode, even though the PC & Writer are UDMA compatible. In PIO mode, the maximum throughput is about 20x reading or writing and this may be the reason why the CD-Writer has to keep rebuffering beyond 20x. You generally can confirm this by putting in a full data CD-R or CD-ROM (no scratches, etc.), running Nero’s CD speed and doing a read test. If the line goes up to about 20x and stops there across, then the drive is stuck in PIO mode.

Checking if DMA is on is different from OS to OS. In Windows 2000 & XP, you go into the Device Manger by going into the System properties (Rightclick My Computer, select the Hardware tab and click on Device Manger…). Under the IDE ATA/ATAPI controller section, go into the first Primary channel (doubleclick it). Click the Advanced Settings tab and check if any of the devices show ‘PIO Mode’ in the Current Transfer Mode. If not, exit from this screen and repeat for the next channel. If you find a device that is in the ‘PIO Mode’, check that the Transfer Mode selection box above it is set to ‘DMA if available’ and change it if necessary.

Zip drives are the only drives I know of that don’t like DMA or Ultra DMA modes, but I only encountered an old 8x CD-ROM that couldn’t handle DMA. If you find devices set to ‘DMA if available’ (Windows 2000 & XP), and are stuck in PIO mode, then it may be worth updating the IDE drivers or try swapping the devices around. I had my DVD-ROM drive get stuck in PIO mode and resolved this by swapping modes with the CD-Writer. :wink:


In WinXP if a drive is stuck in PIO mode, the following procedure usually works without having to swap drives. :cool:

WinXP sometimes spontaneously resets ATAPI devices like burners from DMA mode to PIO mode. When this happens, performance suffers significantly.

This is a bug in WinXP with no real solution as yet, but there is a workaround that will fix it until it happens again:

Go to Device Manager and remove the IDE channel to which the burner is connected and reboot. On system startup, the IDE channel and burner will be redetected and DMA hopefully should be enabled for the drive. Check in Device Manger to confirm that DMA is enabled. :wink:

Well…I`m running win98se

I`ve had the dma box checked in device manager all the time, I was aware of that.

Tried switching ide channels and now it suddenly acts differently…in the “write cd” window (nero) the read buffer stays like between 98% - 100% up to about one fourth of the burning cycle, then it drops gradually…when it hits zero the recorder buffer starts to drop and the next thing is a nice buffer underrun at about the middle of the burn.

The recorder buffer stays at least at 97% as long as I got data in the read buffer so I dont think its a PIO problem...Im really puzzled this time…


It’s entirely possible that even though the DMA box is checked in Device Manager that it is not working properly. As seanbyrne has already suggested, this can often be fixed by downloading and installing the latest IDE drivers for your motherboard chipset.

As you have an older motherboard, there may updated drivers that will fix your problem. It’s worth a try to check it out. :slight_smile: