I just bought a new laptop it configuration -
Intel 915 board (with ICH6 I/O controller)
60 GB HDD (IDE),
DVD combo (Phillips,IDE)
my problem is that when i boot up any Linux
distribution(PHLAK,Knoppix5,Fedora5), my hardisk and DVD drive get
detected as /dev/hdc and /dev/hdd, but transfer rate are damn slow!
i did a hdparm -t /dev/hdc which relvealed a rate of 1.57 MBps and
hdparm -t /dev/hdd revealed 1.7 MBps
hdparm -i /dev/hdc (and hdd) reveales that dma is disabled
my first suspision was a un-enabled dma mode in BIOS, I checked the
BIOS setting, and it already had dma and udma enabled for both devices,
still no linux distribution lets me enable dma.
when i try to enable it manually using "hdparm -d1 /dev/hdc" and on hdd
it gave me permission denied error , no matter what i do i cannot
i googled the problem to find out that the ICH6 I/O chip is actually a
common controller for IDE and SATA devices, so linux detects the
controller as SATA controller and the hard disks as IDE devices and
when it tries to enable dma it fails(due to some technical problem with
libata and piix_ata, i couldnt exactly grasp). To fix the problem, they
suggested turning the "Combined Mode" off (common controller for SATA
and IDE) in the BIOS, but my BIOS doesnt let me turn off this feature.
So Im stuck with no dma and poor transfer rate,
note however that windows works perfectly well, Its a Linux kernel bug
that's that problem
and I am a ardent Linux user and dont prefer Windows
some sites also recommend recompiling kernels using patches .
Is there some other HACK for this problem?
Thanks in advance