Hardware spec

Hi guys,

I'm have the rare opportunity to spec the hardware for a new database
server. It's going to replace an older one, driving a social networking
web application. The current server (a quad opteron with 4Gb of RAM and
80Gb fast SCSI RAID10) is coping with an average load of ranging between
1.5 and 3.5.

The new machine spec I have so far:
    2 x Intel Xeon 2.33 GHz Dual Core Woodcrest Processors
    4 Gb RAM
    5x73 GB Ultra320 SCSI RAID 5 (288 GB storage)

I've heard that RAID 5 is not necessarily the best performer. Also, are
there any special tricks when partition the file system?

Regards,

Willo