Once you have a good understanding of the kind of system you want to set up, the amount of data you want to collect over time, and the type of system your infrastructure (either pre-existing or built specifically for this project) can support, you can select server and work stations that meet your needs.
Most installations require a minimum of 2GB RAM, 250GB hard disk.
At current installations:
HAS Haiti: 600K patients, 4.4 million obs. Average entry of 150 forms and 1400 obs per day. 12GB memory, Dual-Quad Core Intel Xeon 2.33GHz server. Up to 11 users accessing the system simultaneously.
Work stations for retrospective data entry
If you intend for clinicians to enter data on paper forms that are later entered into OpenMRS by data entry clerks, you should estimate the number of work stations you will need based on the amount of data you will enter. As a general rule, it will take a data clerk about one day to enter 80-100 forms with 20 observations per form (this general rule may vary greatly from site to site). For retrospective data entry you may use regular computers that range in cost from $300-$1,000.