optimize and scale up an Apache web site hardware

I need an expert to guide me or even install software, configure servers for me if needed. I have a server now, here is the spec: E7540 (24 cores), 96G RAM, RAID 10 (SA-SCSI 600G x 4) Right now the server (CentOS 5) runs both a DB server (Postgres 8) and a apache server (prefork MPM, not a cluster). I use "top" to check, CPU idle load is between 10-70%, usually 30-40%. RAM is 2-6G free. There is some 40K used swap. DB size is 100G and it is not fast. In terms of the number of process, apache 180-200, DB 30-60. Keepalive and some other optimizations (memcached, 12G RAM on the same server) have been done. I am planning to scale up both economically and strategically. These are my tentative options: 1. replace with a higher spec server 2. build apache cluster, add lower-spec apache servers on top of the current server 3. build DB cluster, add a lower-spec DB server on top of the current server 4. build both apache and DB clusters, replace the current server with lower-spec apache and DB servers In reply, I want to hear your background and approach to handle the project. Right now I suggest to pay you in hour rate.