[OT] bus speed for ata dvd-rw drive

[Gianluca Cecchi]

On Tue, 17 Oct 2006 17:36:00 -0400 Alan Cox wrote:

>For some reason your BIOS appears to have decided the DVD should be in PIO
>mode and we respect that. Make sure the JMB36x boot rom is enabled and if
>its in the main BIOS that IDE bus mastering is BIOS selected.

>Failing that let me know what hdparm -d1 /dev/hde does

Under BIOS setup I have only:
- IDE configuration
where I can only set
SATA configuration [compatible/enhanced/disabled] set to Enhanced but
I think it doesn' influence DVD
Hard disk write protect
IDE detect timeout (set to 35 that is the maximum value, don't know unit)

- Advanced
where I have
JMicron SATA/PATA Controller [enabled/disabled] set obviously to enabled
JMicron Controller Mode [RAID/BASIC/AHCI] set to AHCI that was the
only one with which I could install fc6, otherwise I get no DVD found
after startup...

It seems I have no control over bios rom of JMicron. I see during boot
that the firmware release is 1.06.53 but I don't know if its upgrade
is part of asus bios update.
I have latest bios available from asus installed.
No other options.
hdparm -d1 /dev/hde gives

/dev/hde:
 setting using_dma to 1 (on)
 using_dma    =  1 (on)

In k3b when I open the burn window, it seems it detect maximum of 2X
speed (I see only Auto, 1x, 2x options where I can select speed). When
it starts it says that it will begin at 8x and then actually during
the burning now it goes at 4x (5.5 MB/s).
Apparently with latest kernel 2798 it seems that speed is about 4x
instead of previous 2.6X. I also in the mean time changed the original
80 pin cable (provided with mb) with a 40 pin one. I don't know if
this could influence.
Gianluca