Comment 28 for bug 48556

Must be a problem with ASUS boards. Mine's a P5LD2, and i'm getting the exact same problem. I couldn't even start the liveCD, read thru the errors and it was getting hung up on my DVD writer: "Error 0x01: CD is probably confused".

Booted with "irqpoll" as suggested by the kernel output and was able to get the livecd started and do an install.

Coincidentally, the drive that ubuntu is installed to is on the same IDE channel as the drive. This mobo has 3 channels.. 2 IDE, 2 IDE RAID, and 2 SATA.

Will try ACPI off.