ok, now that I've gotten that out of my system.
servers generally don't require huge throughput, as most of the time they are going to be serving data from their hard drive to the nic, the fastest that link is going to take place is probably 100mbps, most schools don't have gigabit in the schools yet.
redundency and stability are a MUST, this isn't like your home PC where somthing can break and you can live with it for a few days wile a replacement part is aqquired. if this is a server that is relied on, ANY down time is unacceptible from a users point of view.
<warning> this is the section where narzy starts a flame war and is tould how many ways from sunday he is wrong</warning>
before I go any further, and after heading the above warning, I will tell you my background when it comes to educational computing. I've just gotten out of highschool for my exit project I built, set up, and maintained a linux thin client network of 40 concurrent machines that scaled to every computer in the school to try and take the system down. unfortunatly we didn't succeed and the server kept on ticking (this is around 400 clients BTW). I am now a consultant for the school district and one of 2 district wide system tech support folk. and thats my part-time job.
I am a collage student, I also work for comcast on the security team. I'm not trying to flaunt anyone here with my credentials, I am only trying to justify my answer based on my knowlage and avoid getting called nasty names.
what narzy reccomends for hardware:
tho I have faith in the Opteron line of AMD products they are from any industry stand-point un-tested. intel chips have dominated the market for years and have proven to be reliable hardware. if you want to use that logic, then Intel is the way to go. however.
from my personal experiance, AMD 32bit Athlon CPU's have an unfortunate tendancy to burn themselves up. I've run amd systems, they preformed up to par in my opinion however if somthing goes wrong, or the ambiant air gets to hot, the CPU, with stock cooling, unoverclocked will burn. I have not seen (and have not looked) any data on the heat disapation of the opteron line of processors or the thermal protection that is on them. We do run Opteron servers at work, and they work very well. but I want to give you as much info as I can.
tho if you do go with a 64 bit chip from AMD you'd probably want to accompany it with a 64bit OS, and if you plan on running windows 2003 server that can cost a considerable amount more.
CPU: its a draw
memory: the more the better and ECC on a server is a must 2GB is a good starting number for a file server go up as needed.
HD: SCSI Raid 5 array 4 drives minimum one drive set as a hot fail over. aim for 36gb scsi drives
video: most server boards have it onboard if not a cheapo s3 based vc will be fine
sound: not needed
case: up to you, I prefer rackmounts because their versitile, but a chemming design server chassie would be fine as well
PSU: redundant, hotswappable. find one you like.
and on that note, we built a very similar system from dell last year for about 3 grand.
goodluck on your project

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