I am custom building a server to install Elastix 1.6 on to replace my current PC that was originally provided by fonality. The question I have is this: I was told, back in the day, by fonality that at least 1 card (such as an FXO) was required to be installed for the VOIP system to operate properly. This had something to do with 'synchronization or timing' as I recall. I will not be using any analog lines, only ethernet for the VOIP so do I really need an add-in card or was I being over sold? Thanks! p.s. I do have the original FXO card installed in the existing PC but I'm trying to get a completed build done prior to the migration. I don't want to take anything down but simply cut-over.