OK, so I have this big pile of computer parts littering my living room, as I am now putting together two audio computers, porting all my stuff from the POS house computer to my *old* audio computer, and getting my Mac all backed up and ready to give with a clean install to my brother in law. I will keep everyone posted on the builds. Opus- one question- I got the same 4U rack case you suggested (deep sucker...). What are the little pin-down arm thingies suspended in the middle of the case? Never seen that before, and I didn't get a manual.