Original poster said it was on a promise controller (assuming mobo integrated), so the nvraid wouldn't really work on that.
Even if you had a single drive raid 0 array, on an nvraid, my instinct tells me that you could only move it to another mobo with nvraid, it wouldn't be a "normal single drive partition" -- that RAID information, despite its effective nonusage is written into the boot record and won't function like a normal drive. Having never used nvraid, I can't confirm this, though.
BTW, if you have a RAID controller (PCI, PCI Express or PCI-X) you can save your array if you move the controller card
Hopefully on my next build, in the next generation of AMD's socket, I'll be able to get a PCI-Express RAID5 controller and 4 HDs...IDK, maybe like 4x250GB for a 750GB array.