If there is not a lot of e-mail volume, you don't need a BIG system. And for the DATA backup, do you plan to backup on tape, or the server will be a file server...
Because, you have 2 solutions, install a tape backup and do backup everyday or week... Or if you don't have a lot of data to backup. You might only need a RAID array (SCSI, SATA or IDE) to have full data protection and a CD or DVD burner to do backup once a week or once a month.
I strongly recommend you, a basic RAID configuration, because this will save your butt if one of your HDD crash, you will not loose data and productivity.
For the processor, it really depends on the volume of e-mail to process and data to backup. For a small business, you don't need a HIGH-END cpu.
I like this product : :smile:
<A HREF="http://www-1.ibm.com/servers/eserver/opteron/325/more_info.html" target="_new">http://www-1.ibm.com/servers/eserver/opteron/325/more_info.html</A>
Of course, you might say i'm a little bit AMD-biased, and I know it! This is only a suggestion...
Would you buy a GPS enabled soap bar?