Well it sat there with 2 x 2TB HDDs in bays 1 and 2. Not doing anything - quite happy.
So I thought - I'll copy 1TB of photos (about 25MB each) -set it going - after 5 minutes it stopped saying could find a folder - one on the drives had disappeared. Rebooted and drive reconnected. Event viewer showed disk error.
SO - I shut down - put the same 2 drives in my Win 7 i7 pc on 2 SATA connectors. Set them copying - copied exactly same set of photos with no errors. Something amiss somewhere!
Going back!
Mel
Well I reset the BIOS by taking the jumper link off the board when powered down. This also removed the VID file so I had to restore Intelligent provisioning.
But since then (in ACHI mode) - 1 SSD Bay 1, 3HDDs (2x 3TB, 1 x 1TB) in Bays 2, 3, 4) it has been copying to and fro error free. Perhaps I had some corruption somewhere previously?
Now backing it all up to a 6TB USB3 drive - also OK - the 6TB USB3 drive made it run slowly before - now OK.
Mel