Just bought an Aopen CRW-2440 at xmas. I was wondering why the performance is not outstanding (ie it keeps cutting back the write speed on 24x media and it's not a lot faster than my old 12x). So I went onto their site to d/l a firmware & I also d/l the user manual.
I was surprised to find that the drive ships in PIO4-mode and not UDMA mode. Should it make much difference if I remove the "limiting" jumper? (I have a UDMA controller & cables already)

The diff tween PIO 4 & UDMA 2 is minimal but its there.
Do make sure DMA is enabled for all you drives if the system is fairly new & can handle it ok.
http://www.cdrom-guide.com/forums/showthread.php?s=&threadid=6832