It seems that I should do something about that software RAID anyway, I
agree... but:

Neither OS supports software RAID 5.
I haven't done any hacking in Vista, but it recognises the RAID-5 disks
anyway and labels them RAID-5 (failed). This would suggest to me that Vista
does support software RAID-5. At least in the RC2 "Premium" version.

Why would you expect an unsupported option from one OS to work in another
OS?
Since the XP hack does nothing more than enable in XP what was disabled from
NT, I don't think it's a particularly ugly and unsupported hack.
Unofficial hack, yes.
Officially unsupported, yes.
But unofficially supported? It appears so.

Hardware RAID controllers are quite inexpensive and fully supported.
I thought they were rather expensive for simple home use. That's why I opted
for software in the first place. Could you perhaps suggest a useful,
affordable 4-port PCI SATA II controller?


Thanks!