When you're planning a Beowulf, even if its just your first, the purpose is important.
Remember that you could be paralleling everything, not just a CPU. 15 machines with 15 CDRoms equals a "virtual CDRom tower" with 15 CDroms. 15 machines with 15 fast hard drives equals a heck of a lot of bandwidth for high speed data acquisition. 15 machines with 15 "big" hard drives equals a huge virtual hard drive for data storage. 15 machines with 100 meg ether cards plugged into an etherswitch with a fast matrix equals (about) 1.5 gigabit per second of peak transfer rate. 15 machines setup to rip cds into mpegs could be pretty fast. Lets say 1 machine could rip 2 cds per hour, 15 machines could rip 30 cds per hour, or about one every 2 minutes. Or with a fast enough network, cd reader, and hard drive, you could rip the cd on one computer, and then encode all the tracks in parallel, thus you could possibly rip a cd in about 3 minutes, maybe, assuming a 52x cdrom can read an entire audio CD in 1 minute.
