DVD playback slow & choppy

[Kevin Kempter]

On Sunday 19 November 2006 5:27 pm, Mikkel L. Ellertson wrote:
> Kevin Kempter wrote:
> > On Sunday 19 November 2006 4:35 pm, Peter Gordon wrote:
> >> On Sun, 2006-11-19 at 16:20 -0700, Kevin Kempter wrote:
> >>> Hi List;
> >>>
> >>> I just inatalled FC6 on a Pentium 2.2Gz thinkpad with 2G of memory. I
> >>> installed mplayer, the mplayer codecs, xine, kaffeine, etc.  Both Xine
> >>> and Kaffeine play DVD's but the playback is slow & choppy.
> >>>
> >>> Thanks in advance for any help/advice...
>
> <--{snip]-->>
>
> >> Also, is DMA enabled for your DVD drive? If not, this also causes a lot
> >> of CPU usage too. Check that it is set (and set it if not) by running
> >> `/sbin/hdparm -d 1 /dev/dvd`  as root (setting the device node as
> >> appropriate).
> >
> > I tried this:# /sbin/hdparm -d 1 /dev/hdc
> >
> > /dev/hdc:
> >  setting using_dma to 1 (on)
> >  HDIO_SET_DMA failed: Operation not permitted
> >  using_dma    =  0 (off)
>
> Is your hard drive a SATA drive? On my laptop, I had to add
> hdc=noprobe to the boot options. The DVD drive is then handled as
> SCSI device and DMA works. Before I added the option, I had the same
> problems playing DVDs.
>
> Mikkel
> --
>
>   Do not meddle in the affairs of dragons,
> for thou art crunchy and taste good with Ketchup!

This seems to work. Thanks !
Is there are potential issues with adding hdc=noprobe to the boot options ?