The actual RSD detections are done by the sensors, and so usually happen pretty quickly. However sensors don't pass this information back to ePO immediately: this is most likely where the delay is coming from.
The intervals for reporting information back to ePO are configured as part of the RSD sensor policy - I'd have a look at how you have this configured and if necessary tweak the setting for your environment.
Thanks Joe, what would you like to know? As far as i know it is all default setup.
I found the policy and it was set to 1200 seconds on reporting. I set it to 600. But that does explain why it took over 12hours to find the new server we setup.