I recently installed Ubuntu 12.04 LTS on my old Sony Vaio. It's a 32-bit system on the T6570 Intel Duo CPU.

For whatever reason I'm having a long delay in getting the CD/DVD drive to recognize a disk. It worked great under Windows Vista, and still works fine after the CD or DVD has been in the drive for anywhere from 1 to 5 minutes, so I'm pretty sure it's not a hardware issue.

I can watch DVDs, copy CDs, and whatever else I want, but it takes a lot of patience waiting for the system to recognize that there is a disk in the player and tell me what's on it. Once it recognizes that there's something in there and tells me what it is, I can operate normally.