Cannot see Card Reader in My Computer

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I have an XPS420 with twin hard drives setup in a Raid 0 config.  I’ve just installed a third drive, with 2 partitions, on SATA port 4 and BOOM none of my media readers work. I can see the readers in Disk Management but they come up as unallocated. Also in Device Manager I have exclamation marks next to the storage volumes. If I disable the new HDD in the Bios everything returns to normal. It looks to me like Vista is having a problem assigning drive letters to the readers but I have no idea how to fix it. Anyone have any thoughts?

Thanks