Hi all,

I've recently completed a fresh install of Ubuntu Feisty Beta on my laptop. Whereas previously my hard drive and DVD-RW appeared as IDE devices (/dev/hda, /dev/hdd), they now appear as SCSI devices (/dev/sda, /dev/scd0).

This wouldn't be a problem, but video playback is now appallingly choppy, which would tend to suggest some sort of DMA problem. I don't think I can use hdparm with SCSI drives, so does anyone have any ideas?

The laptop is a Celeron 2GHz machine, with Intel chipset (815, I think).

If you need any further info, please let me know.

Many thanks!

Yes, the reason that your ATA drive shows up as SCSI is because, technichally, it is a SCSI device now. Starting with linux kernel version 2.6.19 all ATA drivers are under libata, which appear as /dev/sdX. Now, for backwards compatibility, you can still use the old ATA drivers, but the Ubuntu devs decided(somewhat smart, somewhat stupid, but needs to be done eventually) that for feisty it would use the new drivers.

I have some features of my SATA drives that work with hdparm, but some that don't. Try it out, because it might *just work*

OK, many thanks for that - it clears up some of my confusion. The only thing is, I'm not very familiar with low-level stuff such as IDE / SCSI! To the extent that I don't even know what to google / search for. Anyway, what might I need to do to improve performance? I'm familiar with hdparm, and I believe there's also an equivalent sdparm utility, but it all seems to fly in the face of the Ubuntu 'just works' philosophy (yeah, I've been cossetted by this for the past couple of years!) Thanks again