It will run software RAID, so swaping completely the hardware shouldn't be an issue. Is it expected to have issues with HBAs on the 16x slot of these boards?
I have a desktop system built around 2008 which was pretty decent at that time and has a solid tower case:
Asus M2N32-SLI Deluxe
Athlon64 Am2 6400+
4x2GB DDR2
I would like to build a 15 drive NAS using 3 of those 5-in-3 hotplug cages with the onboard SATA ports and additional PCI SATA...