Hard Drive Blues

About 2 weeks ago my XP box really started acting up on me. I noticed that the game I’m playing lately, Medal of Honor: Pacific Assault, was getting kind of choppy. I then tried to edit some digital video, my other main use for the XP machine, and it didn’t work well either. The AVI capture was choppy and the playback was horrible. I rendered some files as MPEG-2 and burned a DVD, and the video seemed more-or-less OK. That led me to believe I had some sort of video codec trouble, but lots of installing and re-installing failed to remedy the problem.
After testing various things I finally noticed that the HD was operating at about 10% of the expected speed and that SiSoft Sandra reported that the drive was not operating in DMA mode. Seems that XP will automatically switch to PIO mode if it detects a certain number of I/O errors. It will make the switch without any warning; it’s also not immediately obvious how to switch back to DMA.
While there are software solutions that give you direct control of the DMA setting, I just did the old Windows standby: I removed and reinstalled the Primary IDE channel. After 2 reboots the Primary IDE channel was back in DMA mode and everything (so far) seems to be working just as it was. After being prepared to format the HD or start buying new hardware, I was so glad that a simple software solution fixed my problems.