You haven't re-installed driver for the Dell PERC 5/i (or LSI driver if you've flashed it to a MegaRAID), have you? Once you installed the driver, even without the array config. utility you should be able to see them in Disk Management under Windows which you can then assign drive letter as per usual.
have you gone into disk management? the virtual disk may need to be initalized. exactly how did it crash? bad drive or OS level corruption? does the PERC see the drives properly? (e.g. not as a foreign disk configuration)