I can't at the moment. After a FULL reformat Hitachi's boot CD tool reports the drives as having corrupted sectors on a quick scan. I chose the option to repair the sectors rather than an erase. Bad idea? I was hoping it would be faster than an erase. I also have a 1TB Hitachi in the same setup and the diagnostic tool says it's perfectly fine.
I have also swapped some rails and splitters about and put those two drives on a single rail which only has SATA power connectors on it. Plus I have changed all the SATA cables for new latched cables. No difference. it still reported the drive errors. So currently it's doing a repair on one drive and I will see what it reports afterwards. Not happy.