I'm looking to build a NAS server. My initial thoughts were 4xSATA (II?) drives in RAID-5. In addition to the NAS functionality it will be a small AV/spam filtering mail server (~100 mails a day), a web server with php for personal use and possibly an LDAP server running Redhat's LDAP server. It's pretty important to me that the hardware sensors work as the machine will be up 24x7.

Given my budget, and the fact that the machine will be mostly idle, I was thinking software RAID-5 over 4x250GB disks in a hotplug chassis, about 1GB RAM and a Sempron or Celeron D processor and 2xGigE, possibly a dual layer DVD writer for backups of important data.

Any comments on the above would be welcome.

Assuming my thinking as to the platform so far is sound, rhe problem I'm having is figuring out which motherboard and case would be suitable. I'm after the best storage throughput possible with out blowing the bank, so I was thinking SATA-II and I want a chipset that will support hotplugging, although that isn't essential (and would save money .

Is there much difference between SATA and SATA-II?

Can you recommend any motherboard that provide 4xSATA with support for hardware sensors with as full support under Linux as possible?