Sata hdd install issue

Just completed a clean install of vista home premium on a new box with two sata HDD's. Completed the install okay after installing the sata drivers etc..after install the second sata HDD was recognized by windows with correct size etc.. but stated it needed to be formatted to be used so went through the format process. Once complete it disappeared and vista no longer recognizes that it is there. When I reboot and checked the MOBO it is no longer listed as the number 2 sata HDD it's blank. The first sata HDD is there and it boots fine I just can't get the second drive to work. It's a 500GB WD caviar. Any help would be appreciated.