Minimum hardware spec for running asterisk with > 500 exts

Dear All,

What server hardware specification should I use if I want to run Asterisk with more than 500 extensions inside?

is there any theory or best practice that can be used as user standard requirement for running asterisk?

please advise

thanks & regards

We are running 300+ phones on dual 3GHz with 4GB RAM in ESX. Some FOP2 usage. On reload, CPU hits ~70%. With 1 CPU, CPU was pegged at 100% during reloads and would ruin audio. RAM usage has not been an issue.

What codec are you using for audio? How many concurrent calls have you tested it at?