Trying to add a 1TB HDD but system does not see it.

I have a Veriton M480G with a preinstalled 320GB HDD and it seems that the system can only read up to a 450GB HDD. The system does not recognize the 1TB HDD I installed through the windows screen, however, it does see it and recognize it in the bios window. I have plugged it in through a USB port and the system partitioned it into two 450GB drives?? I have tried flashing several different BIOS without any avail. I am having trouble flashing the BIOS that may be the fix (P02-A2).

Does anyone have a fix for this??

Edit: I am running Windows 7 32-bit. The original BIOS was P01-A2. I have successfully loaded Bios P01-B3, but still does not see the 1TB HDD in windows. Trying to flash the BIOS P02-A2 through the American Megatrends program but I get a message that the File ROM ID is incorrect. When I try to open a file to flash, there are not any ROM files to load.