Server Specs for Asterisk SIP + Database + Load Balance Serv

If someone can help me with best suggested specs for following.

I want to run Asterisk as the main thing that will use CPU load.

I will then also run Database, large tables, but very quick basic queries.
e.g. Does ABC record exist in table XYZ.

Load Balance Server. This will be down track in a few months.

Do I really need a SSD drive or SATA will be fine?
Do I need Hardware RAID or software RAID is fine?
Is what I am suggesting below a good setup model (the server I have listed)?

I am looking at
Intel Xeon E3 1245v2 (4 c/ 8 t) 3.4 GHz+ 32 GB RAM
Will this server be best choice?
I would run Proxmox on this server with openVZ / VPS for 1 x Database Server, 1 x Web Server, and 1 x Load Balance Server.

I would then have additional servers such as Kimsufi PS-18 Coreā„¢2 Quad Q6600 / Xeon X3220 - 4GB RAM for the Asterisk servers. I may run up to 5+ of these down the track.

Please share your thoughts.