Don’t run SATA optical drives under AHCI
Sunday, July 6th, 2008 at 5:43 pm
It wasn’t, at least for me…
Shortly after getting it all up and running I found that the system would regularily lock up. But only when burning a DVD which led to a lot of coasters. Thinking it was a driver problem I made sure I was running the latest ones, which partially fixed the problem. Now the burn would still fail, but the system wouldn’t lock up. Instead the drive would just disconnect.
Now I thought it was a hardware problem so I tried different cables, different power connectors and even a different drive (but still a Pioneer). The problem didn’t go away.
At first I researched problems with SATA and optical drives. Many pages ended up pointing to fix (KB928253) that seemed promising. But the fix for that was included in SP1, which I was already running, so I turned to another possibility that involved deleting the UpperFilter and LowerFilter registry entries (KB314060). This seemed like it might be relevant as I had had problems with installing burning software. But continuing the trend, this also didn’t work.
Last weekend I decided to do a fresh install. Partly to see if that would fix the problem, but mostly so I could start with a good install that I hadn’t experimented with. At first I thought this worked. Until the second DVD I tried to burn.
Which brought me to a solution I had discounted. During my research I had found pages talking about how SATA optical drives don’t behave properly under AHCI and the fix was to run them under IDE emulation. I couldn’t see why a recent SATA optical drive wouldn’t work properly under the native SATA mode, haven’t they bothered to implement the spec properly? Or maybe the controller doesn’t?
It has now been a week since I changed back to IDE emulation mode and it as been stable. I haven’t noticed any difference in performance so I’m not really sure what the fuss about AHCI being better is all about.
Aparrently there are motherboards that let you run part of the SATA controller in AHCI and part in IDE emulation. My board, an ASUS P5K Pro, does not support that. But I don’t think that would have affected my choice.