Bootcamp displays black screen on reboot instead of launching the installer
I have a Macbook Pro (early 2011) and I replaced the super drive for an SSD drive. When I try to install window 7 with bootcamp 3.0.4 on the second drive it partitions it fine. When I reboot i hold option and select to install windows 7 from the external dvd drive. It changes to a black screen and doesn't start the windows installer. The DVD continues to spin for a minute or two then stops and nothing else happens.
I've google but nothing. The bootcamp FAQ says it supports installing on a second drive so it should be ok. I also reset the PRAM and SCM but it didn't help. Is there any logging or anything that can be checked for boot issues?
Thanks.
MacBook Pro, Windows 7