I am having a very difficult time installing a new hard drive (WD 160GIG) into my Dell gx150 computer.I installed the new HD and used the Data lifegard tools to partition and format the drive. After nearly 45-60 min, the system will allow me to format and partition and then I put the xp disk in and reboot nothing happens. It says to hit f1 to continue or f2 to enter set up. I hit f1 and it reads NTLDR is missing hit CTRL+ ALT+ DEL to restart