Generally a RAID bios would show up as "Mass Storage CONTROLLER" but the actual RAID partitions would be completly dependent on the controller, mine shows up as Volume0, other ones might show up as RAID array.
Anyways, you're not using RAID but if you have the RAID BIOS enabled, it should find that controller. Check your SCSI/RAID devices in Device Manager. If there are any listed, then you're probably using the RAID BIOS.
It won't really affect anything, though if I plug my SATA DVD burner into the RAID controlled SATA ports it won't be able to boot off it. It can use the same ports to boot from if I change it to AHCI mode, but then I lose the RAID array. I settled by using the 2nd SATA controller in BASE-IDE mode, so now I can boot from that. Point is, if you leave it in RAID setting you will probably not be able to use a SATA burner later unless you have a 2nd SATA controller.
Now, what I would do is download and run HDTach 3, and see what it benchmarks as. If it's as fast as it should be, then I would know that this Mass Storage Device issue is just superficial (is there an icon in the system tray about a device may be removed, like the USB drives have?).
If you were to go into the BIOS and disable the RAID, I'm not sure if you would lose the partition or not.
Check if you have a SCSI/RAID controller device in Device Manager and get back.