Server recommendation for my website

[Bileator]

Hello,

I have a forum website(invision board) and need some inputs to select a dedicated server.
My forum has 8 million posts (Including posts and topics) in total.
Right now i am using Xeon 5260 2 bay chaisis
32 gb ram
400 gb SD
I just want to know how can we determine the server configuration ..based on what factors?
Current issues i am facing is database table crashes....
Any info on cloudarion.com server hosting? Alternatives ? Reviews ?

Thanks