Good point. I looked at Dell and HP outlet and didn't see any i5s that cheap at the moment, but did find this on eBay:
HP Elite 8100 i7 2.8Ghz 8GB ram 320GB HD Q57 Express chipset $249 shipped
HP Elite 8200 i7 3.4Ghz 8GB ram 1TB HD Q67 Express chipset $319 shipped
My preference would be to put a large surveillance drive in the same HP for recording the video footage or use the built-in RAID utility and mirror two large surveillance drives to support the OS and video footage. (maybe different partitions)
HP only lists both boxes supporting up to 1TB drive. (Probably because that's all they offered and tested at the time.) Some research revealed the HP 8200 model supports UEFI which may provide some advantages to using larger surveillance type drives. Is it ok to use the BI box to record video footage or should I be looking at an external NAS? I'm trying to keep hardware costs ~ $1000 and I still need PoE switch and 6 ~ $100 cameras.