Can performance of my PostgreSQL database server be in any way negatively impacted by the system having too much physical RAM. Lets say I have a master database server running PostgreSQL 9.1.2 & we had 96 GB's of physical RAM. Would there be any performance implications to a server having far more RAM than needed to perform it's functions?

I wouldn't think so. What are your configuration settings for memory?

There is no downside to a server having more physical ram than you need. It is a nice problem to have because you can keep your entire database in memory. Allocate enough buffers to hold it all, right after startup initiate something that does table scans of the whole thing to ensure its all in memory quickly and you have an in memory db. Sweet.

There is a downside to allocating more ram to the database than the server has ( swapping / paging etc. ).