This is probably caused by a BIOS issue on your motherboard which limits the amount of the drive to 127 GB I believe. I had a simular problem...First check to see if there is a BIOS update for your MB. If not and if the HDD is not your primary system drive you should be able to use Administrative Tools in Windows to repartition the drive with the full drive capacity.
Go into Administrative Tools - Computer Management - Storage - Disk Management
Then click on the drive - Rt click and choose Delete Partition - Then choose to Create a partion and it should use the entire capacity of the drive. **Keep in mind that will delete all information on the drive.