I have a studio 1536 that was running Vista HP64. Never had one issue. I just upgraded to 7HP64 and I'm getting a funny annoyance.
The safely remove hardware icon lists my main hard drive and the DVD drive with options to safely remove. These drives will never be removed. This has got to be driver related but Windows says they are up to date. Both the C: and the DVD are sata.
I also upgraded my Inspiron 530 tower and had no issue and the tower runs far better than the laptop does. Maybe try a fresh format and install but I've already put so much time putting all my files/programs on. I can't be the only one with this issue. On the tower, both C: and DVD are sata as well.