Damn - that's the impression I was coming to...
The problem I have is that, for some strange reason, this board seems to only allow SATA drives via the Promise RAID/SATA controller chip BIOS , not just as SATA drives.
Therefore I have set them each as 1+0 RAID array - this way they both show up correctly as 500GB drives & I have copied over ghosted OS partitions & data partitions from my PATA drives. These work OK.
If this really is the case with this mboard (and I'm not being thick) then I can't see away of monitoring them for impending failure / high temps etc.