"Promise SuperTrak EX8350 EX ", "Boeing 747", "Adaptec 2820SA", "NAS", oh boy!
I feel like I hit a computer website specialized for admins of big data-centers
When you talk about hardware based RAID 5 (Promise SuperTrak EX8350 EX, Adaptec 2820SA) you are talking about an additional invest of 350-400EUR! Plus the 4 HDs, let's assume 4 cheap 160GB drives at a total of 200 EUR. So you're investing 550EUR and get near 500GB space with RAID 5 safety.
Isn't the solution with 2x500GB plus backup-SW at 220EUR a viable alternative for private use?: Less cost, less noise, less heat, fits into smaller cabinets (I have built 5 computers now, but non could carry 5 HDs), you can do backups each day in the background...
Tell you what: I'd rather invest my money into building a second computer (for the kids/wife) with identical mainboard, a graphics card from the same manufacturer (for driver compatibility) and put the 500GB-clone into that cabinet. Because then I even have a working computer when some other component (like the mainboard) fails. In the last four years I had more defect mainboards than defect drives
And that was when I found out, that even a backup of your system-disk does not really help you, when you don't get an exact mainboard-replacement for your burnt-out one
With all the incompatibility issues today you either send your MB to repair and wait 4 weeks. Because if you buy another mainbooard you end up in the worst case needing new RAM, a new CPU, new power supply, new graphics card or in the best case at least have to reinstall the system SW from scratch

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Thomas (beware: Nikon-fanboy and moderator!)
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