May be your BIOS will not allow your PC to see arge drives.
Do you have SP2 installed?
In Windows, click on Start->Run, enter "regedit".
# Navigate to the HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services\atapi\Parameters registry subkey.
# From the Edit menu, select New, DWORD Value.
# Enter the name EnableBigLba, then press Enter.
# Double-click the new value, set it to 1, then click OK.
# Close the registry editor.
# Restart the machine for the change to take effect.