You need to be more specific.
Is the PC running?
Did you have a c-drive and d-drive and note only a c-drive?
Right-click Computer and see if there is a c-drive and a d-drive. If no d-drive, check Properties of the c-drive to determine size of hard drive. Is it the total size of the hard drive you had originally (should be 500gb, 750th out 1000th).
Also see how much fee space there is on the c-drive via that same Properties approach.
Let me know and I can advise further.