The maximum is usually ~15.4x and the average is ~15x, the curve is mostly flat other than a quick ramp up from about 12x .... I've also noticed that the seek times are really long, around 120ms and the drive itself takes a long time to "spin up".
The chipset is the Nvidia nForce 680i, which is about as new as it gets, the newest drivers are the forceware 97.92 I believe, which is what is installed, I haven't been able to find any reports of slow SATA ODD read speads with this chipset.
There's actually no other software installed on the machine right now other than 2 games and some benchmark programs, so I don't think it will be software or DRM related (haven't even played any CD's in it yet) ... and I haven't had a chance to test DVD's because every time I put one it the nero speed reader gives me different errors.
One other thing, I looked in my event viewer last night and there are constant errors reported such as "The device: device0\cdrom has repoted a bad block" and some other errors I can't remember off the top of my head.