Microsoft dropped support for miniport drivers in 2008R2 (which is why 2008 can see them).  Try the backplane driver: [URL] If that doesn't work, then you will need to do as Geoff suggests, enabling RAID and configuring each disk as a single-disk RAID 0 ... or use Server 2008.
Hi, wonder if anyone can help with this issue we having with our power edge 2850 ( [ADMIN NOTE:  Service Tag removed per privacy policy]) a few days ago raid completely stopped working. Citing the firmware. was corrupt. And I couldn't access the raid utility either. Anyway got hold of the firmware  updater for it which repaired it and updated It. But didn't seem to do much as got same issue upon reboot. Tried reseating all components in the machine. The settings in bios (integrated devices) seems to like changing to "off" randomly. Also cleared the nvram. Anyway we got fed up and decided to scrap the raid and use the six disks as individual and set it in integrated devices in bios to SCSI mode. but this made its own problems too. The OS flatly refuses to see the HDD's (Server 2008 R2) we found it difficult to obtain what we think are non raid drivers but unsure. When we use server 2008 x32 disk it sees some HDD's whys that?  please help we are pressed for time to get it back on as it's our main server.   Was 5x 73GB disks and one 35GB disk. But the 35 GB disk has been swapped for a 145GB disk instead  has 6GB ram too.   We we would now prefer not to use raid and have removed the raid ram, battery and key 
SCSI NO RAID