In activating Ultra DMA mode, my Dell Dimension T700r stopped recognizing the drive completely!
I put the drive in another computer (a Dell Dimension 8300) and after installing the Roxio 6 software, and running Creator Classic, I no longer even got a choice of 8x recording. I got a PowerRec, 4x and 2x options. I chose PowerRec and the damnable thing still recorded at 4x.
My guess is that the pack of 10 DVDs that I purchased were (although rated at 8x were clearly not). No wonder I had issues when I tried recording at 8x on my other computer. I think that I'm going to have to find other 8x media. Plextor sells their own. Maybe those will work?
I don't think that Ultra DMA mode has a thing to do with my problem.
However, I welcome other insights.