cce said:92's have integrated seat collars - this uses a discrete wrap-round collar
Only in catalogue. I had a '92 M700 and it had separate seat collar (Tioga).
I was working in a LBS back then and all the bikes had separate ones. Your bike, however, isn't a '92 model by the colors at least.
It's curious that your frame doesn't have any other markings than the Cannondale logos. In early 90s, 'Dales had lots of different stickers in them, in seat & chain stays, etc. Could yours be built from a frameset ?