Technology Lighthouse

DVD back on the rails

This has nothing to do with development, other than it causing a hold up as I was doing my regular DVD backups. Hopefully documenting my experiences here will help others…

Basically I noticed that my Lite-On ATA DVD drive had started writing at a really slow speed (about 1x) regardless of the setting in the writer software. I ran some checks on the drive’s read performance using a
handy utility called DVD Speed and found that was similarly pedestrian. On top of that, any read/write activity maxed out one of the cores of my cpu and caused all sounds to play back all slow and fragmented. This smacked of PIO mode, so I went into Device Manager and checked the ATA controller that the driver was connected to, but it was showing UDMA mode 5.

I went through various other troubleshooting steps, including deleting the controller and the drive in order to get Windows to re-detect and install them, all to no avail. The more time I spent on it, the more frustrating it became.

After a coffee and a good bit of Googling I came across a site stating that after a certain number of consecutive errors Windows XP can permanently demote a UDMA drive to PIO. Well, I had tried to read a
damaged disk a while back, so that fit. But Device Manager was still claiming that the drive was using UDMA, so I just didn’t feel that my problem was a good match to the description on the site.

However, after more fruitless troubleshooting I decided to give the recommendations on the site a go.

It had a little vbs script to download that would supposedly force XP to reassess my drive. I made sure the drive was empty, downloaded and ran the script then rebooted. Bingo! The drive was back up to normal speed in all read and write operations.

So basically one bad disk had caused XP to semipermanently blacklist my drive as a poor performer and force it into PIO mode, without any indication of this in Device Manager. Not very helpful behavior!

Anyway, if any of this fits problems you’re having with a DVD drive, you should visit the following site and give that wonderful little vbs script a go: http://winhlp.com/node/10 

This entry was posted on Tuesday, October 9th, 2007 at 7:41 am and is filed under Geeks Corner. You can follow any responses to this entry through the RSS 2.0 feed. You can leave a response, or trackback from your own site.