DVD-RAM is supposed to be formated and used the same as any hard disk, so I'm not sure why it wouldn't work in the 2.4 kernel. It's not like CD-RW using UDF packet writing and requiring a kernel patch. I've only attempted DVD-RAM in 2.6.

Not sure about the slow write speed. 0.8-1.0 MB/s sounds terribly slow. I've read that some media performs better than others as well as drives. I've not yet tried writing large files to disk, only tested the operation with average file clusters and had no perceptible lags in performance. I'll give mine a test later with larger files to see what my transfer speeds are. Perhaps your bus is running @ half speed. There is a utility for tuning your bus, but I'm drawing a blank right now as to what it is, or the commands to use it.

I was copying a large file, and by the time I reached around 800Mbytes, the speed has dropped to 400k/s, which was, where I stopped it. Of course there's more head movement on the outer tracks, but also there should be higher write speed.

I don't know what "half bus speed" means, but hdparm says the drive is using udma2 mode.
(I've got an Abit 440BX board, and an lg gsa4040, if it is of any help)

Thanks, I'd be good to see test results on large file copying on a different system.

OK, this is not pretty....
I ran a test on my system using a 664 MB iso file. It took 22 minutes to write, resulting in approx 515 KB/sec write speed. Yes, this sux.
My platform is a 4 year old Tyan s1854 MB w/ PIII-600, 256 MB pc133 ram, WD-400 hd connected to primary IDE master w/ no slave & LG GSA-4120B connected to secondary IDE master w/ no slave. dvd drive is udma-33.

Other operations seem to speed along so I doubt the bus or drive is the problem.
This will take some more looking into. I wonder if the slow performance could be caused by the disk requiring pre-format before writing data blocks to the disk. during the write operation, I noticed the thing would write a block and then pause for a minute or so before going into another write operation. weird