minimum system requierments for server with mods?

[CyberMan]

Can someone write me back all the requierments to the server harware for heavily modded factorio session?

[Zavian]

A potato computer running a 64 bit OS with around 4GB ram is enough to host a multiplayer game for a small number of players and a small base. (Well it also wants a network connection. Depending on your isp, you might also find that your home internet connection is not suitable for hosting multiplayer games). More players, bigger bases and larger maps mean you will want more RAM and faster CPUs. For multiplayer megabases, you probably want a cpu nearly as fast as the slowest client cpu. (That way UPS will drop on the server before the game becomes unplayable for the client with the slowest cpu). RAM usage probably depends more on how many chunks are explored, and how many entities they contain, plus the number of players.