Argh I hate it when windows does this.
When you install windows on a 2 drive setup originally, windows choses for itself where to put the bootmgr info, and it doesn't necessarily use the drive you put the OS on.
Chances are it put it on your storage drive last time, and now this time you've installed, it detected the old boot info and combined them.
If this is the case, you select the old one and it should fail.