RAM Requirements per session

We are considering running Oracle 7.3.X and NT 4.0/3.51 on a Compaq5000. I give this information, although it may or may not be useful.

The question I have is in estimating the Box we need to run this on. We are trying to determine the amount of RAM we need to start with. We have current and future concurrent session numbers. Is there a ballpark factor for the memory required to support 1 session. This is for the PMON(?), the fixed SGA has all been estimated. We simply need the variable growth per user.

Any information would be helpful as we are making WAGs in determining the configuration proposal.

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