40 gigs is plenty for Win7 and
Cubase. I can't see any point of installing your DAW onto HDDs if it's going to be your most used application. There's a thread about SSDs in audio recording on gearslutz
, you may want to look it up. I was actually going to get a 32GB SSD for Win7 and Sonar. I did a bit of research on that and it looks like even a 32 gig SSD would be enough. Just turn off hibernation, disable/reduce page file and you should be fine. And don't bother with partitioning your SSD.