What criteria should I consider when determining the hardware specs for a disk imaging station?

Question

The person who asked the question at #digpres14 was thinking specifically of the tower that powers the disk imaging station rather than all the peripherals. Another way of framing the question is what are the bare minimum specs (RAM, processor, ports)?

Answer 1

From #digpres2014:

At BitCurator, I have found that more RAM makes a huge difference.  It may be a huge amount of work, but you could fire up a VM, give it different amounts of RAM, and do some benchmarking.  It can handle this much imaging at this speed, etc.