With a DB server, your going to want to pimp it out. Fast SCSI disks, and a lot of RAM. On an IIS server, you could get away with just a P4/1GB RAM and a normal IDE HD. But all this depends on what your going to be putting on them.
You have asked a very open ended question here to which I could probably write a good few thousand words, can you be a bit more specific as to what you want to configure them with, and what you're running on them?
What you're using them to host would be a good starting point
█ Dan Kitchen | Technical Director | Razorblue
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