I think I've finally sussed-out what sme linux is up to.
After formatting both hdds via dos, I put them together on a raid card mirrored as raid 1. Linux, bizarrely seems to have used only one drive - the light on one seems to light up 1,000,000 times more often than on the other.
I believe that both drives would be used if I created 2 "sets" instead of a "pair" of raid drives and then used soft raid. Keeping the drives on the raid card offers an advantage in that it keeps my only 2 ide sockets free.
I checked with my supplier and found the cards were made by
www.avlab.com.tw (WF84F - Ultra ATA 133 PCI RAID) who, sadly, don't seem to have bothered with a Linux driver.
Now, my question: If I use soft raid and sebsequently add more drives, will Linux then plunder the extra storage in extensions to its raid system?
Rhys