Cavium ThunderX Processors used for PostgreSQL?

I was shopping around for a dedicated server and I noticed a plan which
uses 2X Cavium ThunderX processors which gives me a total of 96 cores.

I use PostgreSQL + PgBouncer which accepts many connections at a time. I
have my current one to accept maximum connections of 1000, but it never
goes above 200 active connections but the traffic to the system is always
increasing and I want to have the hardware to handle it.

It's the first time I see the Cavium ThunderX name. How do these compare to
a machine that has 2 × E5-2640 v3? I noticed the Cavium ThunderX is a lot
cheaper, but it's not a known name.

What would I get better results with 2X Cavium ThunderX processors with 96
cores or 2 × E5-2640 v3 with 16 cores?