Sometimes, hardware and software inventory will stop processing in SCCM. Increase the MIF file capacity on your SCCM server by modifying this registry key:
HKLM\Software\Microsoft\SMS\Components\SMS_INVENTORY_DATA_LOADER
Max MIF Size
By default, it is set to 5MB (the value is written in hex). Change it to something much larger. I recommend 50MB, which is 3200000 in hex.