Hardware Suggestion under this environment?

Hi

we are planning to use clustered Membase Server for following conditions.

1 Transaction includes about 8~10 libcouchbase APIs (get, set, add etc.)

I was wondering if couchbase could suggest Hardware specs.

(example : 80 QuadCore Clusterable PCs(or servers) with X GB of RAM)

We want to do about 500,000,000 Transactions ~ 1,000,000,000 Transactions per hour

Thank you