To be able to generate a complete Arc Hydro Data Model for your project you need the following software and minimum system requirements:

Software:
Arc GIS Desktop 8.1 or later with ArcEditor or ArcInfo license
ArcGIS Spatial Analyst extension (If geoprocessing a DEM)
Arc Hydro Tool Set
Database Schema
ArcHydroFrameworkSchema, Simplified data model version without time series

FrameworkWithTimeSeriesSchema, Simplified data model version with time series

ArcHydroSchema, Full version of the data model

Hardware:
Minimum of 256 MB RAM
Processor with 1 GHz is recommended